Mercurial > vim
annotate runtime/doc/vim9.txt @ 24128:fcbb1d4df15b v8.2.2605
patch 8.2.2605: Vim9: string index and slice does not include composing chars
Commit: https://github.com/vim/vim/commit/0289a093a4d65c6280a3be118d1d3696d1aa74da
Author: Bram Moolenaar <Bram@vim.org>
Date: Sun Mar 14 18:40:19 2021 +0100
patch 8.2.2605: Vim9: string index and slice does not include composing chars
Problem: Vim9: string index and slice does not include composing chars.
Solution: Include composing characters. (issue https://github.com/vim/vim/issues/6563)
| author | Bram Moolenaar <Bram@vim.org> |
|---|---|
| date | Sun, 14 Mar 2021 18:45:03 +0100 |
| parents | 788e10cec9bd |
| children | 4919f2d8d7fd |
| rev | line source |
|---|---|
| 24103 | 1 *vim9.txt* For Vim version 8.2. Last change: 2021 Mar 03 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
2 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
3 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
4 VIM REFERENCE MANUAL by Bram Moolenaar |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
5 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
6 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
7 THIS IS STILL UNDER DEVELOPMENT - ANYTHING CAN BREAK - ANYTHING CAN CHANGE |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
8 |
|
23392
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
9 Vim9 script commands and expressions. *Vim9* *vim9* |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
10 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
11 Most expression help is in |eval.txt|. This file is about the new syntax and |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
12 features in Vim9 script. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
13 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
14 THIS IS STILL UNDER DEVELOPMENT - ANYTHING CAN BREAK - ANYTHING CAN CHANGE |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
15 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
16 |
| 23466 | 17 1. What is Vim9 script? |Vim9-script| |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
18 2. Differences |vim9-differences| |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
19 3. New style functions |fast-functions| |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
20 4. Types |vim9-types| |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
21 5. Namespace, Import and Export |vim9script| |
| 22328 | 22 6. Future work: classes |vim9-classes| |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
23 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
24 9. Rationale |vim9-rationale| |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
25 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
26 ============================================================================== |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
27 |
|
23358
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
28 1. What is Vim9 script? *Vim9-script* |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
29 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
30 THIS IS STILL UNDER DEVELOPMENT - ANYTHING CAN BREAK - ANYTHING CAN CHANGE |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
31 |
| 20241 | 32 Vim script has been growing over time, while preserving backwards |
| 33 compatibility. That means bad choices from the past often can't be changed | |
| 20965 | 34 and compatibility with Vi restricts possible solutions. Execution is quite |
| 20241 | 35 slow, each line is parsed every time it is executed. |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
36 |
| 20241 | 37 The main goal of Vim9 script is to drastically improve performance. This is |
| 38 accomplished by compiling commands into instructions that can be efficiently | |
| 39 executed. An increase in execution speed of 10 to 100 times can be expected. | |
| 40 | |
| 41 A secondary goal is to avoid Vim-specific constructs and get closer to | |
| 42 commonly used programming languages, such as JavaScript, TypeScript and Java. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
43 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
44 The performance improvements can only be achieved by not being 100% backwards |
| 20552 | 45 compatible. For example, making function arguments available in the |
| 46 "a:" dictionary adds quite a lot of overhead. In a Vim9 function this | |
| 47 dictionary is not available. Other differences are more subtle, such as how | |
| 48 errors are handled. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
49 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
50 The Vim9 script syntax and semantics are used in: |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
51 - a function defined with the `:def` command |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
52 - a script file where the first command is `vim9script` |
| 22328 | 53 - an autocommand defined in the context of the above |
|
23938
2a885d095bff
patch 8.2.2511: Vim9: cannot use Vim9 script syntax in some places
Bram Moolenaar <Bram@vim.org>
parents:
23931
diff
changeset
|
54 - a command prefixed with the `vim9cmd` command modifier |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
55 |
| 23573 | 56 When using `:function` in a Vim9 script file the legacy syntax is used, with |
| 57 the highest |scriptversion|. However, this can be confusing and is therefore | |
| 58 discouraged. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
59 |
| 20241 | 60 Vim9 script and legacy Vim script can be mixed. There is no requirement to |
| 22328 | 61 rewrite old scripts, they keep working as before. You may want to use a few |
| 62 `:def` functions for code that needs to be fast. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
63 |
|
23938
2a885d095bff
patch 8.2.2511: Vim9: cannot use Vim9 script syntax in some places
Bram Moolenaar <Bram@vim.org>
parents:
23931
diff
changeset
|
64 *:vim9* *:vim9cmd* |
|
2a885d095bff
patch 8.2.2511: Vim9: cannot use Vim9 script syntax in some places
Bram Moolenaar <Bram@vim.org>
parents:
23931
diff
changeset
|
65 :vim9[cmd] {cmd} |
|
2a885d095bff
patch 8.2.2511: Vim9: cannot use Vim9 script syntax in some places
Bram Moolenaar <Bram@vim.org>
parents:
23931
diff
changeset
|
66 Execute {cmd} using Vim9 script syntax and semantics. |
|
2a885d095bff
patch 8.2.2511: Vim9: cannot use Vim9 script syntax in some places
Bram Moolenaar <Bram@vim.org>
parents:
23931
diff
changeset
|
67 Useful when typing a command and in a legacy script or |
|
2a885d095bff
patch 8.2.2511: Vim9: cannot use Vim9 script syntax in some places
Bram Moolenaar <Bram@vim.org>
parents:
23931
diff
changeset
|
68 function. |
|
2a885d095bff
patch 8.2.2511: Vim9: cannot use Vim9 script syntax in some places
Bram Moolenaar <Bram@vim.org>
parents:
23931
diff
changeset
|
69 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
70 ============================================================================== |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
71 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
72 2. Differences from legacy Vim script *vim9-differences* |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
73 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
74 THIS IS STILL UNDER DEVELOPMENT - ANYTHING CAN BREAK - ANYTHING CAN CHANGE |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
75 |
| 22441 | 76 Overview ~ |
| 77 | |
| 78 Brief summary of the differences you will most often encounter when using Vim9 | |
| 79 script and `:def` functions; details are below: | |
| 80 - Comments start with #, not ": > | |
| 23573 | 81 echo "hello" # comment |
| 22441 | 82 - Using a backslash for line continuation is hardly ever needed: > |
| 23573 | 83 echo "hello " |
| 22441 | 84 .. yourName |
| 85 .. ", how are you?" | |
| 86 - White space is required in many places. | |
| 87 - Assign values without `:let`, declare variables with `:var`: > | |
| 23573 | 88 var count = 0 |
| 22441 | 89 count += 3 |
| 90 - Constants can be declared with `:final` and `:const`: > | |
| 23573 | 91 final matches = [] # add matches |
| 22441 | 92 const names = ['Betty', 'Peter'] # cannot be changed |
| 93 - `:final` cannot be used as an abbreviation of `:finally`. | |
| 94 - Variables and functions are script-local by default. | |
| 95 - Functions are declared with argument types and return type: > | |
| 96 def CallMe(count: number, message: string): bool | |
| 97 - Call functions without `:call`: > | |
| 23573 | 98 writefile(['done'], 'file.txt') |
|
24128
fcbb1d4df15b
patch 8.2.2605: Vim9: string index and slice does not include composing chars
Bram Moolenaar <Bram@vim.org>
parents:
24103
diff
changeset
|
99 - You cannot use `:xit`, `:t`, `:k`, `:append`, `:change`, `:insert`, `:open` |
|
fcbb1d4df15b
patch 8.2.2605: Vim9: string index and slice does not include composing chars
Bram Moolenaar <Bram@vim.org>
parents:
24103
diff
changeset
|
100 or curly-braces names. |
| 22441 | 101 - A range before a command must be prefixed with a colon: > |
| 23573 | 102 :%s/this/that |
| 103 - Unless mentioned specifically, the highest |scriptversion| is used. | |
| 22441 | 104 |
| 105 | |
|
20023
c85d4e173cc9
patch 8.2.0567: Vim9: cannot put comments halfway expressions
Bram Moolenaar <Bram@vim.org>
parents:
20015
diff
changeset
|
106 Comments starting with # ~ |
|
c85d4e173cc9
patch 8.2.0567: Vim9: cannot put comments halfway expressions
Bram Moolenaar <Bram@vim.org>
parents:
20015
diff
changeset
|
107 |
|
21353
fb8c8fcb7b60
patch 8.2.1227: Vim9: allowing both quoted and # comments is confusing
Bram Moolenaar <Bram@vim.org>
parents:
21250
diff
changeset
|
108 In legacy Vim script comments start with double quote. In Vim9 script |
|
fb8c8fcb7b60
patch 8.2.1227: Vim9: allowing both quoted and # comments is confusing
Bram Moolenaar <Bram@vim.org>
parents:
21250
diff
changeset
|
109 comments start with #. > |
|
fb8c8fcb7b60
patch 8.2.1227: Vim9: allowing both quoted and # comments is confusing
Bram Moolenaar <Bram@vim.org>
parents:
21250
diff
changeset
|
110 # declarations |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
111 var count = 0 # number of occurrences |
|
20023
c85d4e173cc9
patch 8.2.0567: Vim9: cannot put comments halfway expressions
Bram Moolenaar <Bram@vim.org>
parents:
20015
diff
changeset
|
112 |
|
21353
fb8c8fcb7b60
patch 8.2.1227: Vim9: allowing both quoted and # comments is confusing
Bram Moolenaar <Bram@vim.org>
parents:
21250
diff
changeset
|
113 The reason is that a double quote can also be the start of a string. In many |
| 21825 | 114 places, especially halfway through an expression with a line break, it's hard |
| 115 to tell what the meaning is, since both a string and a comment can be followed | |
| 116 by arbitrary text. To avoid confusion only # comments are recognized. This | |
| 117 is the same as in shell scripts and Python programs. | |
|
21353
fb8c8fcb7b60
patch 8.2.1227: Vim9: allowing both quoted and # comments is confusing
Bram Moolenaar <Bram@vim.org>
parents:
21250
diff
changeset
|
118 |
|
fb8c8fcb7b60
patch 8.2.1227: Vim9: allowing both quoted and # comments is confusing
Bram Moolenaar <Bram@vim.org>
parents:
21250
diff
changeset
|
119 In Vi # is a command to list text with numbers. In Vim9 script you can use |
|
fb8c8fcb7b60
patch 8.2.1227: Vim9: allowing both quoted and # comments is confusing
Bram Moolenaar <Bram@vim.org>
parents:
21250
diff
changeset
|
120 `:number` for that. > |
|
21516
c7b2ce90c2de
patch 8.2.1308: Vim9: accidentally using "x" causes Vim to exit
Bram Moolenaar <Bram@vim.org>
parents:
21499
diff
changeset
|
121 101 number |
|
21353
fb8c8fcb7b60
patch 8.2.1227: Vim9: allowing both quoted and # comments is confusing
Bram Moolenaar <Bram@vim.org>
parents:
21250
diff
changeset
|
122 |
|
fb8c8fcb7b60
patch 8.2.1227: Vim9: allowing both quoted and # comments is confusing
Bram Moolenaar <Bram@vim.org>
parents:
21250
diff
changeset
|
123 To improve readability there must be a space between a command and the # |
|
23358
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
124 that starts a comment: > |
|
23392
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
125 var name = value # comment |
|
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
126 var name = value# error! |
|
23358
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
127 |
|
23392
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
128 In legacy Vim script # is also used for the alternate file name. In Vim9 |
|
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
129 script you need to use %% instead. Instead of ## use %%% (stands for all |
|
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
130 arguments). |
| 20115 | 131 |
|
20023
c85d4e173cc9
patch 8.2.0567: Vim9: cannot put comments halfway expressions
Bram Moolenaar <Bram@vim.org>
parents:
20015
diff
changeset
|
132 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
133 Vim9 functions ~ |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
134 |
| 20241 | 135 A function defined with `:def` is compiled. Execution is many times faster, |
| 136 often 10x to 100x times. | |
| 137 | |
| 20552 | 138 Many errors are already found when compiling, before the function is executed. |
| 20241 | 139 The syntax is strict, to enforce code that is easy to read and understand. |
| 140 | |
| 23164 | 141 Compilation is done when either of these is encountered: |
| 142 - the first time the function is called | |
| 21991 | 143 - when the `:defcompile` command is encountered in the script where the |
| 144 function was defined | |
| 145 - `:disassemble` is used for the function. | |
| 146 - a function that is compiled calls the function or uses it as a function | |
| 147 reference | |
| 20552 | 148 |
| 149 `:def` has no options like `:function` does: "range", "abort", "dict" or | |
| 23164 | 150 "closure". A `:def` function always aborts on an error (unless `:silent!` was |
| 151 used for the command or inside a `:try` block), does not get a range passed | |
| 23305 | 152 cannot be a "dict" function, and can always be a closure. |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
153 |
| 20241 | 154 The argument types and return type need to be specified. The "any" type can |
| 155 be used, type checking will then be done at runtime, like with legacy | |
| 156 functions. | |
| 157 | |
| 21825 | 158 Arguments are accessed by name, without "a:", just like any other language. |
| 159 There is no "a:" dictionary or "a:000" list. | |
| 20241 | 160 |
| 161 Variable arguments are defined as the last argument, with a name and have a | |
| 21825 | 162 list type, similar to TypeScript. For example, a list of numbers: > |
| 22171 | 163 def MyFunc(...itemlist: list<number>) |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
164 for item in itemlist |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
165 ... |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
166 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
167 |
| 20241 | 168 Functions and variables are script-local by default ~ |
| 20856 | 169 *vim9-scopes* |
| 20115 | 170 When using `:function` or `:def` to specify a new function at the script level |
| 171 in a Vim9 script, the function is local to the script, as if "s:" was | |
|
22494
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
172 prefixed. Using the "s:" prefix is optional. To define a global function or |
|
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
173 variable the "g:" prefix must be used. For functions in an autoload script |
|
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
174 the "name#" prefix is sufficient. > |
|
21550
b0b57d91671c
patch 8.2.1325: Vim9: using Vim9 script for autaload not tested
Bram Moolenaar <Bram@vim.org>
parents:
21516
diff
changeset
|
175 def ThisFunction() # script-local |
|
b0b57d91671c
patch 8.2.1325: Vim9: using Vim9 script for autaload not tested
Bram Moolenaar <Bram@vim.org>
parents:
21516
diff
changeset
|
176 def s:ThisFunction() # script-local |
| 22171 | 177 def g:ThatFunction() # global |
|
21550
b0b57d91671c
patch 8.2.1325: Vim9: using Vim9 script for autaload not tested
Bram Moolenaar <Bram@vim.org>
parents:
21516
diff
changeset
|
178 def scriptname#function() # autoload |
| 20115 | 179 |
|
22494
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
180 When using `:function` or `:def` to specify a nested function inside a `:def` |
|
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
181 function, this nested function is local to the code block it is defined in. |
| 22565 | 182 In a `:def` function it is not possible to define a script-local function. It |
|
22494
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
183 is possible to define a global function by using the "g:" prefix. |
| 20115 | 184 |
| 185 When referring to a function and no "s:" or "g:" prefix is used, Vim will | |
|
22500
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
186 search for the function: |
| 22565 | 187 - in the function scope, in block scopes |
|
22500
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
188 - in the script scope, possibly imported |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
189 - in the list of global functions |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
190 However, it is recommended to always use "g:" to refer to a global function |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
191 for clarity. |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
192 |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
193 In all cases the function must be defined before used. That is when it is |
| 22723 | 194 called, when `:defcompile` causes it to be compiled, or when code that calls |
| 195 it is being compiled (to figure out the return type). | |
| 20241 | 196 |
| 21676 | 197 The result is that functions and variables without a namespace can usually be |
| 20241 | 198 found in the script, either defined there or imported. Global functions and |
| 21676 | 199 variables could be defined anywhere (good luck finding out where!). |
| 20115 | 200 |
| 21825 | 201 Global functions can still be defined and deleted at nearly any time. In |
| 20317 | 202 Vim9 script script-local functions are defined once when the script is sourced |
| 20552 | 203 and cannot be deleted or replaced. |
| 20115 | 204 |
| 23305 | 205 When compiling a function and a function call is encountered for a function |
| 206 that is not (yet) defined, the |FuncUndefined| autocommand is not triggered. | |
| 207 You can use an autoload function if needed, or call a legacy function and have | |
| 208 |FuncUndefined| triggered there. | |
| 209 | |
| 20115 | 210 |
|
23358
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
211 Reloading a Vim9 script clears functions and variables by default ~ |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
212 *vim9-reload* |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
213 When loading a legacy Vim script a second time nothing is removed, the |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
214 commands will replace existing variables and functions and create new ones. |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
215 |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
216 When loading a Vim9 script a second time all existing script-local functions |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
217 and variables are deleted, thus you start with a clean slate. This is useful |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
218 if you are developing a plugin and want to try a new version. If you renamed |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
219 something you don't have to worry about the old name still hanging around. |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
220 |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
221 If you do want to keep items, use: > |
|
23392
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
222 vim9script noclear |
|
23358
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
223 |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
224 You want to use this in scripts that use a `finish` command to bail out at |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
225 some point when loaded again. E.g. when a buffer local option is set: > |
|
23392
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
226 vim9script noclear |
|
23358
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
227 setlocal completefunc=SomeFunc |
|
23392
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
228 if exists('*g:SomeFunc') | finish | endif |
|
23358
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
229 def g:SomeFunc() |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
230 .... |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
231 |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
232 |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
233 Variable declarations with :var, :final and :const ~ |
|
22494
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
234 *vim9-declaration* *:var* |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
235 Local variables need to be declared with `:var`. Local constants need to be |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
236 declared with `:final` or `:const`. We refer to both as "variables" in this |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
237 section. |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
238 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
239 Variables can be local to a script, function or code block: > |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
240 vim9script |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
241 var script_var = 123 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
242 def SomeFunc() |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
243 var func_var = script_var |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
244 if cond |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
245 var block_var = func_var |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
246 ... |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
247 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
248 The variables are only visible in the block where they are defined and nested |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
249 blocks. Once the block ends the variable is no longer accessible: > |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
250 if cond |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
251 var inner = 5 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
252 else |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
253 var inner = 0 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
254 endif |
| 22171 | 255 echo inner # Error! |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
256 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
257 The declaration must be done earlier: > |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
258 var inner: number |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
259 if cond |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
260 inner = 5 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
261 else |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
262 inner = 0 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
263 endif |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
264 echo inner |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
265 |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
266 To intentionally hide a variable from code that follows, a block can be |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
267 used: > |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
268 { |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
269 var temp = 'temp' |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
270 ... |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
271 } |
| 22171 | 272 echo temp # Error! |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
273 |
|
22272
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
274 Declaring a variable with a type but without an initializer will initialize to |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
275 zero, false or empty. |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
276 |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
277 In Vim9 script `:let` cannot be used. An existing variable is assigned to |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
278 without any command. The same for global, window, tab, buffer and Vim |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
279 variables, because they are not really declared. They can also be deleted |
|
21584
d0c76ce48326
patch 8.2.1342: Vim9: accidentally using "t" gives a confusing error
Bram Moolenaar <Bram@vim.org>
parents:
21550
diff
changeset
|
280 with `:unlet`. |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
281 |
| 24024 | 282 Variables, functions and function arguments cannot shadow previously defined |
| 283 or imported variables and functions in the same script file. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
284 Variables may shadow Ex commands, rename the variable if needed. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
285 |
| 20241 | 286 Global variables and user defined functions must be prefixed with "g:", also |
| 287 at the script level. > | |
| 19968 | 288 vim9script |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
289 var script_local = 'text' |
| 21499 | 290 g:global = 'value' |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
291 var Funcref = g:ThatFunction |
| 19968 | 292 |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
293 Since `&opt = value` is now assigning a value to option "opt", ":&" cannot be |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
294 used to repeat a `:substitute` command. |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
295 |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
296 |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
297 Constants ~ |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
298 *vim9-const* *vim9-final* |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
299 How constants work varies between languages. Some consider a variable that |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
300 can't be assigned another value a constant. JavaScript is an example. Others |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
301 also make the value immutable, thus when a constant uses a list, the list |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
302 cannot be changed. In Vim9 we can use both. |
|
22272
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
303 |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
304 `:const` is used for making both the variable and the value a constant. Use |
|
22272
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
305 this for composite structures that you want to make sure will not be modified. |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
306 Example: > |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
307 const myList = [1, 2] |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
308 myList = [3, 4] # Error! |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
309 myList[0] = 9 # Error! |
| 24024 | 310 myList->add(3) # Error! |
|
22494
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
311 < *:final* |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
312 `:final` is used for making only the variable a constant, the value can be |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
313 changed. This is well known from Java. Example: > |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
314 final myList = [1, 2] |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
315 myList = [3, 4] # Error! |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
316 myList[0] = 9 # OK |
| 24024 | 317 myList->add(3) # OK |
|
22272
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
318 |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
319 It is common to write constants as ALL_CAPS, but you don't have to. |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
320 |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
321 The constant only applies to the value itself, not what it refers to. > |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
322 final females = ["Mary"] |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
323 const NAMES = [["John", "Peter"], females] |
|
22272
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
324 NAMES[0] = ["Jack"] # Error! |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
325 NAMES[0][0] = "Jack" # Error! |
|
22272
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
326 NAMES[1] = ["Emma"] # Error! |
| 23573 | 327 NAMES[1][0] = "Emma" # OK, now females[0] == "Emma" |
|
22272
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
328 |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
329 < *E1092* |
| 21499 | 330 Declaring more than one variable at a time, using the unpack notation, is |
| 331 currently not supported: > | |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
332 var [v1, v2] = GetValues() # Error! |
| 21499 | 333 That is because the type needs to be inferred from the list item type, which |
| 334 isn't that easy. | |
| 335 | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
336 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
337 Omitting :call and :eval ~ |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
338 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
339 Functions can be called without `:call`: > |
| 22171 | 340 writefile(lines, 'file') |
| 19303 | 341 Using `:call` is still possible, but this is discouraged. |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
342 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
343 A method call without `eval` is possible, so long as the start is an |
|
24128
fcbb1d4df15b
patch 8.2.2605: Vim9: string index and slice does not include composing chars
Bram Moolenaar <Bram@vim.org>
parents:
24103
diff
changeset
|
344 identifier or can't be an Ex command. For a function either "(" or "->" must |
|
fcbb1d4df15b
patch 8.2.2605: Vim9: string index and slice does not include composing chars
Bram Moolenaar <Bram@vim.org>
parents:
24103
diff
changeset
|
345 be following, without a line break. Examples: > |
|
21516
c7b2ce90c2de
patch 8.2.1308: Vim9: accidentally using "x" causes Vim to exit
Bram Moolenaar <Bram@vim.org>
parents:
21499
diff
changeset
|
346 myList->add(123) |
|
c7b2ce90c2de
patch 8.2.1308: Vim9: accidentally using "x" causes Vim to exit
Bram Moolenaar <Bram@vim.org>
parents:
21499
diff
changeset
|
347 g:myList->add(123) |
|
c7b2ce90c2de
patch 8.2.1308: Vim9: accidentally using "x" causes Vim to exit
Bram Moolenaar <Bram@vim.org>
parents:
21499
diff
changeset
|
348 [1, 2, 3]->Process() |
|
22936
00b0275ffe7f
patch 8.2.2015: Vim9: literal dict #{} is not like any other language
Bram Moolenaar <Bram@vim.org>
parents:
22723
diff
changeset
|
349 {a: 1, b: 2}->Process() |
|
21516
c7b2ce90c2de
patch 8.2.1308: Vim9: accidentally using "x" causes Vim to exit
Bram Moolenaar <Bram@vim.org>
parents:
21499
diff
changeset
|
350 "foobar"->Process() |
|
c7b2ce90c2de
patch 8.2.1308: Vim9: accidentally using "x" causes Vim to exit
Bram Moolenaar <Bram@vim.org>
parents:
21499
diff
changeset
|
351 ("foobar")->Process() |
|
c7b2ce90c2de
patch 8.2.1308: Vim9: accidentally using "x" causes Vim to exit
Bram Moolenaar <Bram@vim.org>
parents:
21499
diff
changeset
|
352 'foobar'->Process() |
|
c7b2ce90c2de
patch 8.2.1308: Vim9: accidentally using "x" causes Vim to exit
Bram Moolenaar <Bram@vim.org>
parents:
21499
diff
changeset
|
353 ('foobar')->Process() |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
354 |
| 21825 | 355 In the rare case there is ambiguity between a function name and an Ex command, |
| 21676 | 356 prepend ":" to make clear you want to use the Ex command. For example, there |
| 357 is both the `:substitute` command and the `substitute()` function. When the | |
| 358 line starts with `substitute(` this will use the function. Prepend a colon to | |
| 359 use the command instead: > | |
|
19481
c27837cbe922
patch 8.2.0298: Vim9 script: cannot start command with a string constant
Bram Moolenaar <Bram@vim.org>
parents:
19473
diff
changeset
|
360 :substitute(pattern (replacement ( |
|
19473
b09afbebffee
patch 8.2.0294: cannot use Ex command that is also a function name
Bram Moolenaar <Bram@vim.org>
parents:
19404
diff
changeset
|
361 |
|
19556
ff5048b0ccfe
patch 8.2.0335: no completion for :disassemble
Bram Moolenaar <Bram@vim.org>
parents:
19523
diff
changeset
|
362 Note that while variables need to be defined before they can be used, |
| 21825 | 363 functions can be called before being defined. This is required to allow |
| 364 for cyclic dependencies between functions. It is slightly less efficient, | |
|
19556
ff5048b0ccfe
patch 8.2.0335: no completion for :disassemble
Bram Moolenaar <Bram@vim.org>
parents:
19523
diff
changeset
|
365 since the function has to be looked up by name. And a typo in the function |
|
21516
c7b2ce90c2de
patch 8.2.1308: Vim9: accidentally using "x" causes Vim to exit
Bram Moolenaar <Bram@vim.org>
parents:
21499
diff
changeset
|
366 name will only be found when the function is called. |
|
19556
ff5048b0ccfe
patch 8.2.0335: no completion for :disassemble
Bram Moolenaar <Bram@vim.org>
parents:
19523
diff
changeset
|
367 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
368 |
| 19968 | 369 Omitting function() ~ |
| 370 | |
| 371 A user defined function can be used as a function reference in an expression | |
| 372 without `function()`. The argument types and return type will then be checked. | |
| 373 The function must already have been defined. > | |
| 374 | |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
375 var Funcref = MyFunction |
| 19968 | 376 |
| 377 When using `function()` the resulting type is "func", a function with any | |
| 378 number of arguments and any return type. The function can be defined later. | |
| 379 | |
| 380 | |
|
23358
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
381 Lambda using => instead of -> ~ |
|
23318
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
382 |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
383 In legacy script there can be confusion between using "->" for a method call |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
384 and for a lambda. Also, when a "{" is found the parser needs to figure out if |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
385 it is the start of a lambda or a dictionary, which is now more complicated |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
386 because of the use of argument types. |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
387 |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
388 To avoid these problems Vim9 script uses a different syntax for a lambda, |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
389 which is similar to Javascript: > |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
390 var Lambda = (arg) => expression |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
391 |
|
23358
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
392 No line break is allowed in the arguments of a lambda up to and including the |
|
23318
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
393 "=>". This is OK: > |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
394 filter(list, (k, v) => |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
395 v > 0) |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
396 This does not work: > |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
397 filter(list, (k, v) |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
398 => v > 0) |
|
23392
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
399 This also does not work: > |
|
23318
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
400 filter(list, (k, |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
401 v) => v > 0) |
|
23392
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
402 But you can use a backslash to concatenate the lines before parsing: > |
|
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
403 filter(list, (k, |
|
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
404 \ v) |
|
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
405 \ => v > 0) |
|
23318
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
406 |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
407 Additionally, a lambda can contain statements in {}: > |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
408 var Lambda = (arg) => { |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
409 g:was_called = 'yes' |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
410 return expression |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
411 } |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
412 NOT IMPLEMENTED YET |
|
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
413 |
| 23737 | 414 *vim9-curly* |
|
23358
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
415 To avoid the "{" of a dictionary literal to be recognized as a statement block |
| 24024 | 416 wrap it in parentheses: > |
|
23358
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
417 var Lambda = (arg) => ({key: 42}) |
|
23318
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
418 |
| 23737 | 419 Also when confused with the start of a command block: > |
| 420 ({ | |
| 421 key: value | |
| 422 })->method() | |
| 423 | |
|
23318
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
424 |
|
19999
844c7646f61b
patch 8.2.0555: Vim9: line continuation is not always needed
Bram Moolenaar <Bram@vim.org>
parents:
19968
diff
changeset
|
425 Automatic line continuation ~ |
|
844c7646f61b
patch 8.2.0555: Vim9: line continuation is not always needed
Bram Moolenaar <Bram@vim.org>
parents:
19968
diff
changeset
|
426 |
|
844c7646f61b
patch 8.2.0555: Vim9: line continuation is not always needed
Bram Moolenaar <Bram@vim.org>
parents:
19968
diff
changeset
|
427 In many cases it is obvious that an expression continues on the next line. In |
|
23392
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
428 those cases there is no need to prefix the line with a backslash (see |
|
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
429 |line-continuation|). For example, when a list spans multiple lines: > |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
430 var mylist = [ |
|
19999
844c7646f61b
patch 8.2.0555: Vim9: line continuation is not always needed
Bram Moolenaar <Bram@vim.org>
parents:
19968
diff
changeset
|
431 'one', |
|
844c7646f61b
patch 8.2.0555: Vim9: line continuation is not always needed
Bram Moolenaar <Bram@vim.org>
parents:
19968
diff
changeset
|
432 'two', |
|
844c7646f61b
patch 8.2.0555: Vim9: line continuation is not always needed
Bram Moolenaar <Bram@vim.org>
parents:
19968
diff
changeset
|
433 ] |
|
20011
628011800942
patch 8.2.0561: Vim9: cannot split function call in multiple lines
Bram Moolenaar <Bram@vim.org>
parents:
19999
diff
changeset
|
434 And when a dict spans multiple lines: > |
|
22936
00b0275ffe7f
patch 8.2.2015: Vim9: literal dict #{} is not like any other language
Bram Moolenaar <Bram@vim.org>
parents:
22723
diff
changeset
|
435 var mydict = { |
|
20011
628011800942
patch 8.2.0561: Vim9: cannot split function call in multiple lines
Bram Moolenaar <Bram@vim.org>
parents:
19999
diff
changeset
|
436 one: 1, |
|
628011800942
patch 8.2.0561: Vim9: cannot split function call in multiple lines
Bram Moolenaar <Bram@vim.org>
parents:
19999
diff
changeset
|
437 two: 2, |
|
628011800942
patch 8.2.0561: Vim9: cannot split function call in multiple lines
Bram Moolenaar <Bram@vim.org>
parents:
19999
diff
changeset
|
438 } |
|
628011800942
patch 8.2.0561: Vim9: cannot split function call in multiple lines
Bram Moolenaar <Bram@vim.org>
parents:
19999
diff
changeset
|
439 Function call: > |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
440 var result = Func( |
|
20011
628011800942
patch 8.2.0561: Vim9: cannot split function call in multiple lines
Bram Moolenaar <Bram@vim.org>
parents:
19999
diff
changeset
|
441 arg1, |
|
628011800942
patch 8.2.0561: Vim9: cannot split function call in multiple lines
Bram Moolenaar <Bram@vim.org>
parents:
19999
diff
changeset
|
442 arg2 |
|
628011800942
patch 8.2.0561: Vim9: cannot split function call in multiple lines
Bram Moolenaar <Bram@vim.org>
parents:
19999
diff
changeset
|
443 ) |
|
628011800942
patch 8.2.0561: Vim9: cannot split function call in multiple lines
Bram Moolenaar <Bram@vim.org>
parents:
19999
diff
changeset
|
444 |
|
20982
bb49b5090a9c
patch 8.2.1042: Vim9: cannot put an operator on the next line
Bram Moolenaar <Bram@vim.org>
parents:
20965
diff
changeset
|
445 For binary operators in expressions not in [], {} or () a line break is |
|
bb49b5090a9c
patch 8.2.1042: Vim9: cannot put an operator on the next line
Bram Moolenaar <Bram@vim.org>
parents:
20965
diff
changeset
|
446 possible just before or after the operator. For example: > |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
447 var text = lead |
|
20982
bb49b5090a9c
patch 8.2.1042: Vim9: cannot put an operator on the next line
Bram Moolenaar <Bram@vim.org>
parents:
20965
diff
changeset
|
448 .. middle |
|
bb49b5090a9c
patch 8.2.1042: Vim9: cannot put an operator on the next line
Bram Moolenaar <Bram@vim.org>
parents:
20965
diff
changeset
|
449 .. end |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
450 var total = start + |
| 23573 | 451 end - |
|
20013
bf377a9ffccb
patch 8.2.0562: Vim9: cannot split an expression into multiple lines
Bram Moolenaar <Bram@vim.org>
parents:
20011
diff
changeset
|
452 correction |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
453 var result = positive |
|
20982
bb49b5090a9c
patch 8.2.1042: Vim9: cannot put an operator on the next line
Bram Moolenaar <Bram@vim.org>
parents:
20965
diff
changeset
|
454 ? PosFunc(arg) |
|
bb49b5090a9c
patch 8.2.1042: Vim9: cannot put an operator on the next line
Bram Moolenaar <Bram@vim.org>
parents:
20965
diff
changeset
|
455 : NegFunc(arg) |
|
20013
bf377a9ffccb
patch 8.2.0562: Vim9: cannot split an expression into multiple lines
Bram Moolenaar <Bram@vim.org>
parents:
20011
diff
changeset
|
456 |
| 21499 | 457 For a method call using "->" and a member using a dot, a line break is allowed |
| 458 before it: > | |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
459 var result = GetBuilder() |
| 20965 | 460 ->BuilderSetWidth(333) |
| 461 ->BuilderSetHeight(777) | |
| 462 ->BuilderBuild() | |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
463 var result = MyDict |
| 21499 | 464 .member |
| 20965 | 465 |
|
23392
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
466 For commands that have an argument that is a list of commands, the | character |
|
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
467 at the start of the line indicates line continuation: > |
|
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
468 autocmd BufNewFile *.match if condition |
|
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
469 | echo 'match' |
|
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
470 | endif |
|
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
471 |
|
20982
bb49b5090a9c
patch 8.2.1042: Vim9: cannot put an operator on the next line
Bram Moolenaar <Bram@vim.org>
parents:
20965
diff
changeset
|
472 < *E1050* |
|
bb49b5090a9c
patch 8.2.1042: Vim9: cannot put an operator on the next line
Bram Moolenaar <Bram@vim.org>
parents:
20965
diff
changeset
|
473 To make it possible for the operator at the start of the line to be |
| 21250 | 474 recognized, it is required to put a colon before a range. This will add |
|
20982
bb49b5090a9c
patch 8.2.1042: Vim9: cannot put an operator on the next line
Bram Moolenaar <Bram@vim.org>
parents:
20965
diff
changeset
|
475 "start" and print: > |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
476 var result = start |
|
20982
bb49b5090a9c
patch 8.2.1042: Vim9: cannot put an operator on the next line
Bram Moolenaar <Bram@vim.org>
parents:
20965
diff
changeset
|
477 + print |
| 21250 | 478 Like this: > |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
479 var result = start + print |
| 21250 | 480 |
|
20982
bb49b5090a9c
patch 8.2.1042: Vim9: cannot put an operator on the next line
Bram Moolenaar <Bram@vim.org>
parents:
20965
diff
changeset
|
481 This will assign "start" and print a line: > |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
482 var result = start |
|
20982
bb49b5090a9c
patch 8.2.1042: Vim9: cannot put an operator on the next line
Bram Moolenaar <Bram@vim.org>
parents:
20965
diff
changeset
|
483 :+ print |
|
19999
844c7646f61b
patch 8.2.0555: Vim9: line continuation is not always needed
Bram Moolenaar <Bram@vim.org>
parents:
19968
diff
changeset
|
484 |
| 23047 | 485 Note that the colon is not required for the |+cmd| argument: > |
| 486 edit +6 fname | |
| 487 | |
|
20015
c001ee73519a
patch 8.2.0563: Vim9: cannot split a function line
Bram Moolenaar <Bram@vim.org>
parents:
20013
diff
changeset
|
488 It is also possible to split a function header over multiple lines, in between |
|
c001ee73519a
patch 8.2.0563: Vim9: cannot split a function line
Bram Moolenaar <Bram@vim.org>
parents:
20013
diff
changeset
|
489 arguments: > |
|
c001ee73519a
patch 8.2.0563: Vim9: cannot split a function line
Bram Moolenaar <Bram@vim.org>
parents:
20013
diff
changeset
|
490 def MyFunc( |
|
c001ee73519a
patch 8.2.0563: Vim9: cannot split a function line
Bram Moolenaar <Bram@vim.org>
parents:
20013
diff
changeset
|
491 text: string, |
|
c001ee73519a
patch 8.2.0563: Vim9: cannot split a function line
Bram Moolenaar <Bram@vim.org>
parents:
20013
diff
changeset
|
492 separator = '-' |
|
c001ee73519a
patch 8.2.0563: Vim9: cannot split a function line
Bram Moolenaar <Bram@vim.org>
parents:
20013
diff
changeset
|
493 ): string |
|
c001ee73519a
patch 8.2.0563: Vim9: cannot split a function line
Bram Moolenaar <Bram@vim.org>
parents:
20013
diff
changeset
|
494 |
| 23305 | 495 Since a continuation line cannot be easily recognized the parsing of commands |
|
23318
c76240efdf02
patch 8.2.2204: Vim9: using -> both for method and lambda is confusing
Bram Moolenaar <Bram@vim.org>
parents:
23305
diff
changeset
|
496 has been made stricter. E.g., because of the error in the first line, the |
| 23305 | 497 second line is seen as a separate command: > |
| 498 popup_create(some invalid expression, { | |
| 499 exit_cb: Func}) | |
| 500 Now "exit_cb: Func})" is actually a valid command: save any changes to the | |
| 501 file "_cb: Func})" and exit. To avoid this kind of mistake in Vim9 script | |
| 502 there must be white space between most command names and the argument. | |
| 503 | |
| 23666 | 504 However, the argument of a command that is a command won't be recognized. For |
| 505 example, after "windo echo expr" a line break inside "expr" will not be seen. | |
| 506 | |
| 23305 | 507 |
| 21250 | 508 Notes: |
| 509 - "enddef" cannot be used at the start of a continuation line, it ends the | |
| 510 current function. | |
| 511 - No line break is allowed in the LHS of an assignment. Specifically when | |
| 512 unpacking a list |:let-unpack|. This is OK: > | |
| 22171 | 513 [var1, var2] = |
| 21250 | 514 Func() |
| 515 < This does not work: > | |
| 22171 | 516 [var1, |
| 21250 | 517 var2] = |
| 518 Func() | |
| 519 - No line break is allowed in between arguments of an `:echo`, `:execute` and | |
| 520 similar commands. This is OK: > | |
| 22171 | 521 echo [1, |
| 21250 | 522 2] [3, |
| 523 4] | |
| 524 < This does not work: > | |
| 22171 | 525 echo [1, 2] |
| 21250 | 526 [3, 4] |
|
19999
844c7646f61b
patch 8.2.0555: Vim9: line continuation is not always needed
Bram Moolenaar <Bram@vim.org>
parents:
19968
diff
changeset
|
527 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
528 No curly braces expansion ~ |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
529 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
530 |curly-braces-names| cannot be used. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
531 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
532 |
|
22936
00b0275ffe7f
patch 8.2.2015: Vim9: literal dict #{} is not like any other language
Bram Moolenaar <Bram@vim.org>
parents:
22723
diff
changeset
|
533 Dictionary literals ~ |
|
00b0275ffe7f
patch 8.2.2015: Vim9: literal dict #{} is not like any other language
Bram Moolenaar <Bram@vim.org>
parents:
22723
diff
changeset
|
534 |
|
00b0275ffe7f
patch 8.2.2015: Vim9: literal dict #{} is not like any other language
Bram Moolenaar <Bram@vim.org>
parents:
22723
diff
changeset
|
535 Traditionally Vim has supported dictionary literals with a {} syntax: > |
|
00b0275ffe7f
patch 8.2.2015: Vim9: literal dict #{} is not like any other language
Bram Moolenaar <Bram@vim.org>
parents:
22723
diff
changeset
|
536 let dict = {'key': value} |
|
00b0275ffe7f
patch 8.2.2015: Vim9: literal dict #{} is not like any other language
Bram Moolenaar <Bram@vim.org>
parents:
22723
diff
changeset
|
537 |
|
23088
285cde4b8d0e
patch 8.2.2090: Vim9: dict does not accept a key in quotes
Bram Moolenaar <Bram@vim.org>
parents:
23047
diff
changeset
|
538 Later it became clear that using a simple text key is very common, thus |
|
285cde4b8d0e
patch 8.2.2090: Vim9: dict does not accept a key in quotes
Bram Moolenaar <Bram@vim.org>
parents:
23047
diff
changeset
|
539 literal dictionaries were introduced in a backwards compatible way: > |
|
22936
00b0275ffe7f
patch 8.2.2015: Vim9: literal dict #{} is not like any other language
Bram Moolenaar <Bram@vim.org>
parents:
22723
diff
changeset
|
540 let dict = #{key: value} |
|
00b0275ffe7f
patch 8.2.2015: Vim9: literal dict #{} is not like any other language
Bram Moolenaar <Bram@vim.org>
parents:
22723
diff
changeset
|
541 |
|
23088
285cde4b8d0e
patch 8.2.2090: Vim9: dict does not accept a key in quotes
Bram Moolenaar <Bram@vim.org>
parents:
23047
diff
changeset
|
542 However, this #{} syntax is unlike any existing language. As it turns out |
|
285cde4b8d0e
patch 8.2.2090: Vim9: dict does not accept a key in quotes
Bram Moolenaar <Bram@vim.org>
parents:
23047
diff
changeset
|
543 that using a literal key is much more common than using an expression, and |
|
22936
00b0275ffe7f
patch 8.2.2015: Vim9: literal dict #{} is not like any other language
Bram Moolenaar <Bram@vim.org>
parents:
22723
diff
changeset
|
544 considering that JavaScript uses this syntax, using the {} form for dictionary |
|
23088
285cde4b8d0e
patch 8.2.2090: Vim9: dict does not accept a key in quotes
Bram Moolenaar <Bram@vim.org>
parents:
23047
diff
changeset
|
545 literals is considered a much more useful syntax. In Vim9 script the {} form |
|
22936
00b0275ffe7f
patch 8.2.2015: Vim9: literal dict #{} is not like any other language
Bram Moolenaar <Bram@vim.org>
parents:
22723
diff
changeset
|
546 uses literal keys: > |
| 23666 | 547 var dict = {key: value} |
|
22936
00b0275ffe7f
patch 8.2.2015: Vim9: literal dict #{} is not like any other language
Bram Moolenaar <Bram@vim.org>
parents:
22723
diff
changeset
|
548 |
|
23088
285cde4b8d0e
patch 8.2.2090: Vim9: dict does not accept a key in quotes
Bram Moolenaar <Bram@vim.org>
parents:
23047
diff
changeset
|
549 This works for alphanumeric characters, underscore and dash. If you want to |
|
285cde4b8d0e
patch 8.2.2090: Vim9: dict does not accept a key in quotes
Bram Moolenaar <Bram@vim.org>
parents:
23047
diff
changeset
|
550 use another character, use a single or double quoted string: > |
| 23666 | 551 var dict = {'key with space': value} |
| 552 var dict = {"key\twith\ttabs": value} | |
| 553 var dict = {'': value} # empty key | |
|
23088
285cde4b8d0e
patch 8.2.2090: Vim9: dict does not accept a key in quotes
Bram Moolenaar <Bram@vim.org>
parents:
23047
diff
changeset
|
554 |
|
285cde4b8d0e
patch 8.2.2090: Vim9: dict does not accept a key in quotes
Bram Moolenaar <Bram@vim.org>
parents:
23047
diff
changeset
|
555 In case the key needs to be an expression, square brackets can be used, just |
|
285cde4b8d0e
patch 8.2.2090: Vim9: dict does not accept a key in quotes
Bram Moolenaar <Bram@vim.org>
parents:
23047
diff
changeset
|
556 like in JavaScript: > |
| 23666 | 557 var dict = {["key" .. nr]: value} |
|
22936
00b0275ffe7f
patch 8.2.2015: Vim9: literal dict #{} is not like any other language
Bram Moolenaar <Bram@vim.org>
parents:
22723
diff
changeset
|
558 |
|
23827
7e0d8f1cae7d
patch 8.2.2455: Vim9: key type for literal dict and indexing is inconsistent
Bram Moolenaar <Bram@vim.org>
parents:
23737
diff
changeset
|
559 The key type can be string, number, bool or float. Other types result in an |
|
7e0d8f1cae7d
patch 8.2.2455: Vim9: key type for literal dict and indexing is inconsistent
Bram Moolenaar <Bram@vim.org>
parents:
23737
diff
changeset
|
560 error. A number can be given with and without the []: > |
|
7e0d8f1cae7d
patch 8.2.2455: Vim9: key type for literal dict and indexing is inconsistent
Bram Moolenaar <Bram@vim.org>
parents:
23737
diff
changeset
|
561 var dict = {123: 'without', [456]: 'with'} |
|
7e0d8f1cae7d
patch 8.2.2455: Vim9: key type for literal dict and indexing is inconsistent
Bram Moolenaar <Bram@vim.org>
parents:
23737
diff
changeset
|
562 echo dict |
|
7e0d8f1cae7d
patch 8.2.2455: Vim9: key type for literal dict and indexing is inconsistent
Bram Moolenaar <Bram@vim.org>
parents:
23737
diff
changeset
|
563 {'456': 'with', '123': 'without'} |
|
7e0d8f1cae7d
patch 8.2.2455: Vim9: key type for literal dict and indexing is inconsistent
Bram Moolenaar <Bram@vim.org>
parents:
23737
diff
changeset
|
564 |
|
22936
00b0275ffe7f
patch 8.2.2015: Vim9: literal dict #{} is not like any other language
Bram Moolenaar <Bram@vim.org>
parents:
22723
diff
changeset
|
565 |
|
23978
54b2aa1f0d42
patch 8.2.2531: Vim9: the :k command is obscure
Bram Moolenaar <Bram@vim.org>
parents:
23974
diff
changeset
|
566 No :xit, :t, :k, :append, :change or :insert ~ |
| 19303 | 567 |
|
21584
d0c76ce48326
patch 8.2.1342: Vim9: accidentally using "t" gives a confusing error
Bram Moolenaar <Bram@vim.org>
parents:
21550
diff
changeset
|
568 These commands are too easily confused with local variable names. |
|
d0c76ce48326
patch 8.2.1342: Vim9: accidentally using "t" gives a confusing error
Bram Moolenaar <Bram@vim.org>
parents:
21550
diff
changeset
|
569 Instead of `:x` or `:xit` you can use `:exit`. |
|
d0c76ce48326
patch 8.2.1342: Vim9: accidentally using "t" gives a confusing error
Bram Moolenaar <Bram@vim.org>
parents:
21550
diff
changeset
|
570 Instead of `:t` you can use `:copy`. |
|
23978
54b2aa1f0d42
patch 8.2.2531: Vim9: the :k command is obscure
Bram Moolenaar <Bram@vim.org>
parents:
23974
diff
changeset
|
571 Instead of `:k` you can use `:mark`. |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
572 |
| 19303 | 573 |
| 574 Comparators ~ | |
| 575 | |
| 576 The 'ignorecase' option is not used for comparators that use strings. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
577 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
578 |
| 23666 | 579 For loop ~ |
| 580 | |
| 581 Legacy Vim script has some tricks to make a for loop over a list handle | |
| 582 deleting items at the current or previous item. In Vim9 script it just uses | |
| 583 the index, if items are deleted then items in the list will be skipped. | |
| 584 Example legacy script: > | |
| 585 let l = [1, 2, 3, 4] | |
| 586 for i in l | |
| 587 echo i | |
| 588 call remove(l, index(l, i)) | |
| 589 endfor | |
| 590 Would echo: | |
| 591 1 | |
| 592 2 | |
| 593 3 | |
| 594 4 | |
| 595 In compiled Vim9 script you get: | |
| 596 1 | |
| 597 3 | |
| 598 Generally, you should not change the list that is iterated over. Make a copy | |
| 599 first if needed. | |
| 600 | |
| 601 | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
602 White space ~ |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
603 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
604 Vim9 script enforces proper use of white space. This is no longer allowed: > |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
605 var name=234 # Error! |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
606 var name= 234 # Error! |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
607 var name =234 # Error! |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
608 There must be white space before and after the "=": > |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
609 var name = 234 # OK |
| 21250 | 610 White space must also be put before the # that starts a comment after a |
| 611 command: > | |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
612 var name = 234# Error! |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
613 var name = 234 # OK |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
614 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
615 White space is required around most operators. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
616 |
| 23466 | 617 White space is required in a sublist (list slice) around the ":", except at |
| 618 the start and end: > | |
| 619 otherlist = mylist[v : count] # v:count has a different meaning | |
| 620 otherlist = mylist[:] # make a copy of the List | |
| 621 otherlist = mylist[v :] | |
| 622 otherlist = mylist[: v] | |
| 623 | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
624 White space is not allowed: |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
625 - Between a function name and the "(": > |
| 23666 | 626 Func (arg) # Error! |
| 627 Func | |
| 22171 | 628 \ (arg) # Error! |
| 23666 | 629 Func |
| 630 (arg) # Error! | |
| 631 Func(arg) # OK | |
| 632 Func( | |
| 633 arg) # OK | |
| 634 Func( | |
| 635 arg # OK | |
| 636 ) | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
637 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
638 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
639 Conditions and expressions ~ |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
640 |
|
22500
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
641 Conditions and expressions are mostly working like they do in other languages. |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
642 Some values are different from legacy Vim script: |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
643 value legacy Vim script Vim9 script ~ |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
644 0 falsy falsy |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
645 1 truthy truthy |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
646 99 truthy Error! |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
647 "0" falsy Error! |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
648 "99" truthy Error! |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
649 "text" falsy Error! |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
650 |
|
22500
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
651 For the "??" operator and when using "!" then there is no error, every value |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
652 is either falsy or truthy. This is mostly like JavaScript, except that an |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
653 empty list and dict is falsy: |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
654 |
|
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
655 type truthy when ~ |
| 23466 | 656 bool true, v:true or 1 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
657 number non-zero |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
658 float non-zero |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
659 string non-empty |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
660 blob non-empty |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
661 list non-empty (different from JavaScript) |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
662 dictionary non-empty (different from JavaScript) |
| 19968 | 663 func when there is a function name |
| 23466 | 664 special true or v:true |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
665 job when not NULL |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
666 channel when not NULL |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
667 class when not NULL |
| 23466 | 668 object when not NULL (TODO: when isTrue() returns true) |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
669 |
|
22494
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
670 The boolean operators "||" and "&&" expect the values to be boolean, zero or |
|
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
671 one: > |
|
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
672 1 || false == true |
|
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
673 0 || 1 == true |
|
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
674 0 || false == false |
|
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
675 1 && true == true |
|
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
676 0 && 1 == false |
|
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
677 8 || 0 Error! |
|
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
678 'yes' && 0 Error! |
|
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
679 [] || 99 Error! |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
680 |
|
22494
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
681 When using "!" for inverting, there is no error for using any type and the |
|
22500
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
682 result is a boolean. "!!" can be used to turn any value into boolean: > |
| 23573 | 683 !'yes' == false |
|
22500
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
684 !![] == false |
| 23573 | 685 !![1, 2, 3] == true |
|
22494
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
686 |
|
4c21f7f6f9e3
patch 8.2.1795: Vim9: operators && and || have a confusing result
Bram Moolenaar <Bram@vim.org>
parents:
22441
diff
changeset
|
687 When using "`.."` for string concatenation arguments of simple types are |
|
22500
ef8a3177edc1
patch 8.2.1798: Vim9: trinary operator condition is too permissive
Bram Moolenaar <Bram@vim.org>
parents:
22494
diff
changeset
|
688 always converted to string: > |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
689 'hello ' .. 123 == 'hello 123' |
| 23466 | 690 'hello ' .. v:true == 'hello true' |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
691 |
|
21771
fcf978444298
patch 8.2.1435: Vim9: always converting to string for ".." leads to mistakes
Bram Moolenaar <Bram@vim.org>
parents:
21717
diff
changeset
|
692 Simple types are string, float, special and bool. For other types |string()| |
|
fcf978444298
patch 8.2.1435: Vim9: always converting to string for ".." leads to mistakes
Bram Moolenaar <Bram@vim.org>
parents:
21717
diff
changeset
|
693 can be used. |
|
23497
2247a2ce3630
patch 8.2.2291: Vim9: cannot use "null" for v:null
Bram Moolenaar <Bram@vim.org>
parents:
23466
diff
changeset
|
694 *false* *true* *null* |
|
2247a2ce3630
patch 8.2.2291: Vim9: cannot use "null" for v:null
Bram Moolenaar <Bram@vim.org>
parents:
23466
diff
changeset
|
695 In Vim9 script one can use "true" for v:true, "false" for v:false and "null" |
|
2247a2ce3630
patch 8.2.2291: Vim9: cannot use "null" for v:null
Bram Moolenaar <Bram@vim.org>
parents:
23466
diff
changeset
|
696 for v:null. When converting a boolean to a string "false" and "true" are |
|
2247a2ce3630
patch 8.2.2291: Vim9: cannot use "null" for v:null
Bram Moolenaar <Bram@vim.org>
parents:
23466
diff
changeset
|
697 used, not "v:false" and "v:true" like in legacy script. "v:none" is not |
|
2247a2ce3630
patch 8.2.2291: Vim9: cannot use "null" for v:null
Bram Moolenaar <Bram@vim.org>
parents:
23466
diff
changeset
|
698 changed, it is only used in JSON and has no equivalent in other languages. |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
699 |
|
24128
fcbb1d4df15b
patch 8.2.2605: Vim9: string index and slice does not include composing chars
Bram Moolenaar <Bram@vim.org>
parents:
24103
diff
changeset
|
700 Indexing a string with [idx] or taking a slice with [idx : idx] uses character |
|
fcbb1d4df15b
patch 8.2.2605: Vim9: string index and slice does not include composing chars
Bram Moolenaar <Bram@vim.org>
parents:
24103
diff
changeset
|
701 indexes instead of byte indexes. Composing characters are included. |
|
fcbb1d4df15b
patch 8.2.2605: Vim9: string index and slice does not include composing chars
Bram Moolenaar <Bram@vim.org>
parents:
24103
diff
changeset
|
702 Example: > |
| 21825 | 703 echo 'bár'[1] |
| 704 In legacy script this results in the character 0xc3 (an illegal byte), in Vim9 | |
| 705 script this results in the string 'á'. | |
| 23573 | 706 A negative index is counting from the end, "[-1]" is the last character. |
| 23666 | 707 To exclude the last character use |slice()|. |
| 23573 | 708 If the index is out of range then an empty string results. |
| 709 | |
| 710 In legacy script "++var" and "--var" would be silently accepted and have no | |
| 711 effect. This is an error in Vim9 script. | |
| 712 | |
| 713 Numbers starting with zero are not considered to be octal, only numbers | |
| 714 starting with "0o" are octal: "0o744". |scriptversion-4| | |
| 21825 | 715 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
716 |
| 21093 | 717 What to watch out for ~ |
| 718 *vim9-gotchas* | |
| 719 Vim9 was designed to be closer to often used programming languages, but at the | |
| 720 same time tries to support the legacy Vim commands. Some compromises had to | |
| 721 be made. Here is a summary of what might be unexpected. | |
| 722 | |
| 723 Ex command ranges need to be prefixed with a colon. > | |
| 23666 | 724 -> legacy Vim: shifts the previous line to the right |
| 725 ->func() Vim9: method call in a continuation line | |
| 726 :-> Vim9: shifts the previous line to the right | |
| 21093 | 727 |
| 23666 | 728 %s/a/b legacy Vim: substitute on all lines |
| 21093 | 729 x = alongname |
| 23666 | 730 % another Vim9: modulo operator in a continuation line |
| 731 :%s/a/b Vim9: substitute on all lines | |
| 732 't legacy Vim: jump to mark t | |
| 733 'text'->func() Vim9: method call | |
| 734 :'t Vim9: jump to mark t | |
| 21093 | 735 |
| 21676 | 736 Some Ex commands can be confused with assignments in Vim9 script: > |
| 23666 | 737 g:name = value # assignment |
| 738 g:pattern:cmd # invalid command - ERROR | |
| 739 :g:pattern:cmd # :global command | |
| 21676 | 740 |
| 21093 | 741 Functions defined with `:def` compile the whole function. Legacy functions |
| 742 can bail out, and the following lines are not parsed: > | |
| 743 func Maybe() | |
| 744 if !has('feature') | |
| 745 return | |
| 746 endif | |
| 747 use-feature | |
| 748 endfunc | |
| 749 Vim9 functions are compiled as a whole: > | |
| 750 def Maybe() | |
| 751 if !has('feature') | |
| 752 return | |
| 753 endif | |
| 23573 | 754 use-feature # May give a compilation error |
| 21093 | 755 enddef |
| 756 For a workaround, split it in two functions: > | |
| 757 func Maybe() | |
| 758 if has('feature') | |
| 23666 | 759 call MaybeInner() |
| 21093 | 760 endif |
| 761 endfunc | |
| 762 if has('feature') | |
| 763 def MaybeInner() | |
| 764 use-feature | |
| 765 enddef | |
| 766 endif | |
| 22171 | 767 Or put the unsupported code inside an `if` with a constant expression that |
| 21991 | 768 evaluates to false: > |
| 769 def Maybe() | |
| 770 if has('feature') | |
| 771 use-feature | |
| 772 endif | |
| 773 enddef | |
| 23573 | 774 < *vim9-user-command* |
| 23666 | 775 Another side effect of compiling a function is that the presence of a user |
| 23573 | 776 command is checked at compile time. If the user command is defined later an |
| 777 error will result. This works: > | |
| 778 command -nargs=1 MyCommand echom <q-args> | |
| 779 def Works() | |
| 780 MyCommand 123 | |
| 781 enddef | |
| 782 This will give an error for "MyCommand" not being defined: > | |
| 783 def Works() | |
| 784 command -nargs=1 MyCommand echom <q-args> | |
| 785 MyCommand 123 | |
| 786 enddef | |
| 787 A workaround is to invoke the command indirectly with `:execute`: > | |
| 788 def Works() | |
| 789 command -nargs=1 MyCommand echom <q-args> | |
| 790 execute 'MyCommand 123' | |
| 791 enddef | |
| 792 | |
| 21991 | 793 Note that for unrecognized commands there is no check for "|" and a following |
| 794 command. This will give an error for missing `endif`: > | |
| 795 def Maybe() | |
| 796 if has('feature') | use-feature | endif | |
| 797 enddef | |
| 21093 | 798 |
| 23305 | 799 Other differences ~ |
| 800 | |
| 801 Patterns are used like 'magic' is set, unless explicitly overruled. | |
| 802 The 'edcompatible' option value is not used. | |
| 803 The 'gdefault' option value is not used. | |
| 804 | |
| 24103 | 805 You may also find this wiki useful. It was written by an early adoptor of |
| 806 Vim9 script: https://github.com/lacygoill/wiki/blob/master/vim/vim9.md | |
| 23305 | 807 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
808 ============================================================================== |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
809 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
810 3. New style functions *fast-functions* |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
811 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
812 THIS IS STILL UNDER DEVELOPMENT - ANYTHING CAN BREAK - ANYTHING CAN CHANGE |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
813 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
814 *:def* |
| 21825 | 815 :def[!] {name}([arguments])[: {return-type}] |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
816 Define a new function by the name {name}. The body of |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
817 the function follows in the next lines, until the |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
818 matching `:enddef`. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
819 |
|
19904
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
820 When {return-type} is omitted or is "void" the |
|
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
821 function is not expected to return anything. |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
822 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
823 {arguments} is a sequence of zero or more argument |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
824 declarations. There are three forms: |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
825 {name}: {type} |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
826 {name} = {value} |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
827 {name}: {type} = {value} |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
828 The first form is a mandatory argument, the caller |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
829 must always provide them. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
830 The second and third form are optional arguments. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
831 When the caller omits an argument the {value} is used. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
832 |
| 20856 | 833 The function will be compiled into instructions when |
| 21499 | 834 called, or when `:disassemble` or `:defcompile` is |
| 835 used. Syntax and type errors will be produced at that | |
| 836 time. | |
| 20856 | 837 |
| 21499 | 838 It is possible to nest `:def` inside another `:def` or |
| 839 `:function` up to about 50 levels deep. | |
| 19303 | 840 |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
841 [!] is used as with `:function`. Note that |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
842 script-local functions cannot be deleted or redefined |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
843 later in Vim9 script. They can only be removed by |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
844 reloading the same script. |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
845 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
846 *:enddef* |
| 21499 | 847 :enddef End of a function defined with `:def`. It should be on |
| 848 a line by its own. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
849 |
|
24128
fcbb1d4df15b
patch 8.2.2605: Vim9: string index and slice does not include composing chars
Bram Moolenaar <Bram@vim.org>
parents:
24103
diff
changeset
|
850 You may also find this wiki useful. It was written by an early adoptor of |
|
fcbb1d4df15b
patch 8.2.2605: Vim9: string index and slice does not include composing chars
Bram Moolenaar <Bram@vim.org>
parents:
24103
diff
changeset
|
851 Vim9 script: https://github.com/lacygoill/wiki/blob/master/vim/vim9.md |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
852 |
|
19473
b09afbebffee
patch 8.2.0294: cannot use Ex command that is also a function name
Bram Moolenaar <Bram@vim.org>
parents:
19404
diff
changeset
|
853 If the script the function is defined in is Vim9 script, then script-local |
|
b09afbebffee
patch 8.2.0294: cannot use Ex command that is also a function name
Bram Moolenaar <Bram@vim.org>
parents:
19404
diff
changeset
|
854 variables can be accessed without the "s:" prefix. They must be defined |
| 20856 | 855 before the function is compiled. If the script the function is defined in is |
| 856 legacy script, then script-local variables must be accessed with the "s:" | |
| 21991 | 857 prefix and they do not need to exist (they can be deleted any time). |
|
19473
b09afbebffee
patch 8.2.0294: cannot use Ex command that is also a function name
Bram Moolenaar <Bram@vim.org>
parents:
19404
diff
changeset
|
858 |
| 20552 | 859 *:defc* *:defcompile* |
| 860 :defc[ompile] Compile functions defined in the current script that | |
| 861 were not compiled yet. | |
| 862 This will report errors found during the compilation. | |
|
19473
b09afbebffee
patch 8.2.0294: cannot use Ex command that is also a function name
Bram Moolenaar <Bram@vim.org>
parents:
19404
diff
changeset
|
863 |
| 19404 | 864 *:disa* *:disassemble* |
| 865 :disa[ssemble] {func} Show the instructions generated for {func}. | |
| 866 This is for debugging and testing. | |
|
19556
ff5048b0ccfe
patch 8.2.0335: no completion for :disassemble
Bram Moolenaar <Bram@vim.org>
parents:
19523
diff
changeset
|
867 Note that for command line completion of {func} you |
|
ff5048b0ccfe
patch 8.2.0335: no completion for :disassemble
Bram Moolenaar <Bram@vim.org>
parents:
19523
diff
changeset
|
868 can prepend "s:" to find script-local functions. |
| 19404 | 869 |
| 23737 | 870 :disa[ssemble]! {func} Like `:disassemble` but with the instructions used for |
| 871 profiling. | |
| 872 | |
| 21250 | 873 Limitations ~ |
| 874 | |
| 875 Local variables will not be visible to string evaluation. For example: > | |
|
23358
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
876 def MapList(): list<string> |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
877 var list = ['aa', 'bb', 'cc', 'dd'] |
| 21250 | 878 return range(1, 2)->map('list[v:val]') |
| 879 enddef | |
| 880 | |
| 881 The map argument is a string expression, which is evaluated without the | |
| 882 function scope. Instead, use a lambda: > | |
|
23358
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
883 def MapList(): list<string> |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
884 var list = ['aa', 'bb', 'cc', 'dd'] |
|
23358
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
885 return range(1, 2)->map(( _, v) => list[v]) |
| 21250 | 886 enddef |
| 887 | |
|
23358
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
888 The same is true for commands that are not compiled, such as `:global`. |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
889 For these the backtick expansion can be used. Example: > |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
890 def Replace() |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
891 var newText = 'blah' |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
892 g/pattern/s/^/`=newText`/ |
|
b3142fc0a414
patch 8.2.2222: Vim9: cannot keep script variables when reloading
Bram Moolenaar <Bram@vim.org>
parents:
23318
diff
changeset
|
893 enddef |
| 21250 | 894 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
895 ============================================================================== |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
896 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
897 4. Types *vim9-types* |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
898 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
899 THIS IS STILL UNDER DEVELOPMENT - ANYTHING CAN BREAK - ANYTHING CAN CHANGE |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
900 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
901 The following builtin types are supported: |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
902 bool |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
903 number |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
904 float |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
905 string |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
906 blob |
|
19904
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
907 list<{type}> |
|
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
908 dict<{type}> |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
909 job |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
910 channel |
| 19646 | 911 func |
| 19968 | 912 func: {type} |
|
19904
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
913 func({type}, ...) |
|
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
914 func({type}, ...): {type} |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
915 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
916 Not supported yet: |
|
19904
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
917 tuple<a: {type}, b: {type}, ...> |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
918 |
|
19904
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
919 These types can be used in declarations, but no value will have this type: |
| 21499 | 920 {type}|{type} {not implemented yet} |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
921 void |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
922 any |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
923 |
|
19904
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
924 There is no array type, use list<{type}> instead. For a list constant an |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
925 efficient implementation is used that avoids allocating lot of small pieces of |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
926 memory. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
927 |
|
19904
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
928 A partial and function can be declared in more or less specific ways: |
|
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
929 func any kind of function reference, no type |
| 19968 | 930 checking for arguments or return value |
|
19904
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
931 func: {type} any number and type of arguments with specific |
|
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
932 return type |
| 19968 | 933 func({type}) function with argument type, does not return |
|
19904
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
934 a value |
| 19968 | 935 func({type}): {type} function with argument type and return type |
| 936 func(?{type}) function with type of optional argument, does | |
| 937 not return a value | |
| 938 func(...{type}) function with type of variable number of | |
| 939 arguments, does not return a value | |
| 940 func({type}, ?{type}, ...{type}): {type} | |
| 941 function with: | |
| 942 - type of mandatory argument | |
| 943 - type of optional argument | |
| 944 - type of variable number of arguments | |
| 945 - return type | |
|
19904
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
946 |
|
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
947 If the return type is "void" the function does not return a value. |
|
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
948 |
|
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
949 The reference can also be a |Partial|, in which case it stores extra arguments |
|
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
950 and/or a dictionary, which are not visible to the caller. Since they are |
|
bd4f91762d0f
patch 8.2.0508: Vim9: func and partial types not done yet
Bram Moolenaar <Bram@vim.org>
parents:
19646
diff
changeset
|
951 called in the same way the declaration is the same. |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
952 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
953 Custom types can be defined with `:type`: > |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
954 :type MyList list<string> |
|
21715
571832713efa
patch 8.2.1407: Vim9: type of list and dict only depends on first item
Bram Moolenaar <Bram@vim.org>
parents:
21676
diff
changeset
|
955 Custom types must start with a capital letter, to avoid name clashes with |
|
571832713efa
patch 8.2.1407: Vim9: type of list and dict only depends on first item
Bram Moolenaar <Bram@vim.org>
parents:
21676
diff
changeset
|
956 builtin types added later, similarly to user functions. |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
957 {not implemented yet} |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
958 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
959 And classes and interfaces can be used as types: > |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
960 :class MyClass |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
961 :var mine: MyClass |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
962 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
963 :interface MyInterface |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
964 :var mine: MyInterface |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
965 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
966 :class MyTemplate<Targ> |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
967 :var mine: MyTemplate<number> |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
968 :var mine: MyTemplate<string> |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
969 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
970 :class MyInterface<Targ> |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
971 :var mine: MyInterface<number> |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
972 :var mine: MyInterface<string> |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
973 {not implemented yet} |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
974 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
975 |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
976 Variable types and type casting ~ |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
977 *variable-types* |
|
21717
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
978 Variables declared in Vim9 script or in a `:def` function have a type, either |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
979 specified explicitly or inferred from the initialization. |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
980 |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
981 Global, buffer, window and tab page variables do not have a specific type, the |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
982 value can be changed at any time, possibly changing the type. Therefore, in |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
983 compiled code the "any" type is assumed. |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
984 |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
985 This can be a problem when the "any" type is undesired and the actual type is |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
986 expected to always be the same. For example, when declaring a list: > |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
987 var l: list<number> = [1, g:two] |
| 23305 | 988 At compile time Vim doesn't know the type of "g:two" and the expression type |
| 989 becomes list<any>. An instruction is generated to check the list type before | |
| 990 doing the assignment, which is a bit inefficient. | |
| 991 *type-casting* | |
| 992 To avoid this, use a type cast: > | |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
993 var l: list<number> = [1, <number>g:two] |
| 23305 | 994 The compiled code will then only check that "g:two" is a number and give an |
| 995 error if it isn't. This is called type casting. | |
|
21717
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
996 |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
997 The syntax of a type cast is: "<" {type} ">". There cannot be white space |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
998 after the "<" or before the ">" (to avoid them being confused with |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
999 smaller-than and bigger-than operators). |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
1000 |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
1001 The semantics is that, if needed, a runtime type check is performed. The |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
1002 value is not actually changed. If you need to change the type, e.g. to change |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
1003 it to a string, use the |string()| function. Or use |str2nr()| to convert a |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
1004 string to a number. |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
1005 |
|
ef3b31d510d2
patch 8.2.1408: Vim9: type casting not supported
Bram Moolenaar <Bram@vim.org>
parents:
21715
diff
changeset
|
1006 |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1007 Type inference ~ |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1008 *type-inference* |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1009 In general: Whenever the type is clear it can be omitted. For example, when |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1010 declaring a variable and giving it a value: > |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1011 var name = 0 # infers number type |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1012 var name = 'hello' # infers string type |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1013 |
|
21715
571832713efa
patch 8.2.1407: Vim9: type of list and dict only depends on first item
Bram Moolenaar <Bram@vim.org>
parents:
21676
diff
changeset
|
1014 The type of a list and dictionary comes from the common type of the values. |
|
571832713efa
patch 8.2.1407: Vim9: type of list and dict only depends on first item
Bram Moolenaar <Bram@vim.org>
parents:
21676
diff
changeset
|
1015 If the values all have the same type, that type is used for the list or |
|
571832713efa
patch 8.2.1407: Vim9: type of list and dict only depends on first item
Bram Moolenaar <Bram@vim.org>
parents:
21676
diff
changeset
|
1016 dictionary. If there is a mix of types, the "any" type is used. > |
|
571832713efa
patch 8.2.1407: Vim9: type of list and dict only depends on first item
Bram Moolenaar <Bram@vim.org>
parents:
21676
diff
changeset
|
1017 [1, 2, 3] list<number> |
|
571832713efa
patch 8.2.1407: Vim9: type of list and dict only depends on first item
Bram Moolenaar <Bram@vim.org>
parents:
21676
diff
changeset
|
1018 ['a', 'b', 'c'] list<string> |
|
571832713efa
patch 8.2.1407: Vim9: type of list and dict only depends on first item
Bram Moolenaar <Bram@vim.org>
parents:
21676
diff
changeset
|
1019 [1, 'x', 3] list<any> |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1020 |
| 21991 | 1021 |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1022 Stricter type checking ~ |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1023 *type-checking* |
| 21991 | 1024 In legacy Vim script, where a number was expected, a string would be |
| 1025 automatically converted to a number. This was convenient for an actual number | |
| 1026 such as "123", but leads to unexpected problems (but no error message) if the | |
| 1027 string doesn't start with a number. Quite often this leads to hard-to-find | |
| 1028 bugs. | |
| 1029 | |
| 1030 In Vim9 script this has been made stricter. In most places it works just as | |
| 22171 | 1031 before, if the value used matches the expected type. There will sometimes be |
| 1032 an error, thus breaking backwards compatibility. For example: | |
| 21991 | 1033 - Using a number other than 0 or 1 where a boolean is expected. *E1023* |
| 1034 - Using a string value when setting a number options. | |
| 1035 - Using a number where a string is expected. *E1024* | |
| 1036 | |
| 23573 | 1037 One consequence is that the item type of a list or dict given to map() must |
| 24024 | 1038 not change. This will give an error in Vim9 script: > |
| 23573 | 1039 map([1, 2, 3], (i, v) => 'item ' .. i) |
| 24024 | 1040 E1012: Type mismatch; expected number but got string |
| 1041 Instead use |mapnew()|. If the item type was determined to be "any" it can | |
| 1042 change to a more specific type. E.g. when a list of mixed types gets changed | |
| 1043 to a list of numbers. | |
| 1044 Same for |extend()|, use |extendnew()| instead, and for |flatten()|, use | |
| 1045 |flattennew()| instead. | |
| 23573 | 1046 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1047 ============================================================================== |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1048 |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1049 5. Namespace, Import and Export |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1050 *vim9script* *vim9-export* *vim9-import* |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1051 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1052 THIS IS STILL UNDER DEVELOPMENT - ANYTHING CAN BREAK - ANYTHING CAN CHANGE |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1053 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1054 A Vim9 script can be written to be imported. This means that everything in |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1055 the script is local, unless exported. Those exported items, and only those |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1056 items, can then be imported in another script. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1057 |
| 21991 | 1058 You can cheat by using the global namespace explicitly. We will assume here |
| 1059 that you don't do that. | |
| 1060 | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1061 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1062 Namespace ~ |
|
23392
517fca70e084
patch 8.2.2239: Vim9: concatenating lines with backslash is inconvenient
Bram Moolenaar <Bram@vim.org>
parents:
23360
diff
changeset
|
1063 *vim9-namespace* |
| 19303 | 1064 To recognize a file that can be imported the `vim9script` statement must |
|
23974
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1065 appear as the first statement in the file (see |vim9-mix| for an exception). |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1066 It tells Vim to interpret the script in its own namespace, instead of the |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1067 global namespace. If a file starts with: > |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1068 vim9script |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1069 var myvar = 'yes' |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1070 Then "myvar" will only exist in this file. While without `vim9script` it would |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1071 be available as `g:myvar` from any other script and function. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1072 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1073 The variables at the file level are very much like the script-local "s:" |
| 20115 | 1074 variables in legacy Vim script, but the "s:" is omitted. And they cannot be |
| 1075 deleted. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1076 |
| 20115 | 1077 In Vim9 script the global "g:" namespace can still be used as before. And the |
| 1078 "w:", "b:" and "t:" namespaces. These have in common that variables are not | |
| 1079 declared and they can be deleted. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1080 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1081 A side effect of `:vim9script` is that the 'cpoptions' option is set to the |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1082 Vim default value, like with: > |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1083 :set cpo&vim |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1084 One of the effects is that |line-continuation| is always enabled. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1085 The original value of 'cpoptions' is restored at the end of the script. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1086 |
|
23974
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1087 *vim9-mix* |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1088 There is one way to use both legacy and Vim9 syntax in one script file: > |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1089 " comments may go here |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1090 if !has('vim9script') |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1091 " legacy script commands go here |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1092 finish |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1093 endif |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1094 vim9script |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1095 # Vim9 script commands go here |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1096 This allows for writing a script that takes advantage of the Vim9 script |
| 24024 | 1097 syntax if possible, but will also work on a Vim version without it. |
|
23974
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1098 |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1099 This can only work in two ways: |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1100 1. The "if" statement evaluates to false, the commands up to `endif` are |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1101 skipped and `vim9script` is then the first command actually executed. |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1102 2. The "if" statement evaluates to true, the commands up to `endif` are |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1103 executed and `finish` bails out before reaching `vim9script`. |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1104 |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1105 TODO: The "vim9script" feature does not exist yet, it will only be added once |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1106 the Vim9 script syntax has been fully implemented. |
|
d4f7e4138544
patch 8.2.2529: Vim9: Not possible to use legacy and Vim9 script in one file
Bram Moolenaar <Bram@vim.org>
parents:
23938
diff
changeset
|
1107 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1108 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1109 Export ~ |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1110 *:export* *:exp* |
| 21499 | 1111 Exporting an item can be written as: > |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1112 export const EXPORTED_CONST = 1234 |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1113 export var someValue = ... |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1114 export final someValue = ... |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1115 export const someValue = ... |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1116 export def MyFunc() ... |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1117 export class MyClass ... |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1118 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1119 As this suggests, only constants, variables, `:def` functions and classes can |
| 24103 | 1120 be exported. {not implemented yet: export class} |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1121 |
| 20856 | 1122 *E1042* |
| 1123 `:export` can only be used in Vim9 script, at the script level. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1124 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1125 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1126 Import ~ |
| 20965 | 1127 *:import* *:imp* *E1094* |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1128 The exported items can be imported individually in another Vim9 script: > |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1129 import EXPORTED_CONST from "thatscript.vim" |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1130 import MyClass from "myclass.vim" |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1131 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1132 To import multiple items at the same time: > |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1133 import {someValue, MyClass} from "thatscript.vim" |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1134 |
| 19303 | 1135 In case the name is ambiguous, another name can be specified: > |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1136 import MyClass as ThatClass from "myclass.vim" |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1137 import {someValue, MyClass as ThatClass} from "myclass.vim" |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1138 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1139 To import all exported items under a specific identifier: > |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1140 import * as That from 'thatscript.vim' |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1141 |
| 22328 | 1142 {not implemented yet: using "This as That"} |
| 1143 | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1144 Then you can use "That.EXPORTED_CONST", "That.someValue", etc. You are free |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1145 to choose the name "That", but it is highly recommended to use the name of the |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1146 script file to avoid confusion. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1147 |
| 22171 | 1148 `:import` can also be used in legacy Vim script. The imported items still |
| 1149 become script-local, even when the "s:" prefix is not given. | |
| 1150 | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1151 The script name after `import` can be: |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1152 - A relative path, starting "." or "..". This finds a file relative to the |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1153 location of the script file itself. This is useful to split up a large |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1154 plugin into several files. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1155 - An absolute path, starting with "/" on Unix or "D:/" on MS-Windows. This |
| 22723 | 1156 will rarely be used. |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1157 - A path not being relative or absolute. This will be found in the |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1158 "import" subdirectories of 'runtimepath' entries. The name will usually be |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1159 longer and unique, to avoid loading the wrong file. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1160 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1161 Once a vim9 script file has been imported, the result is cached and used the |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1162 next time the same script is imported. It will not be read again. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1163 *:import-cycle* |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1164 The `import` commands are executed when encountered. If that script (directly |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1165 or indirectly) imports the current script, then items defined after the |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1166 `import` won't be processed yet. Therefore cyclic imports can exist, but may |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1167 result in undefined items. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1168 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1169 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1170 Import in an autoload script ~ |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1171 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1172 For optimal startup speed, loading scripts should be postponed until they are |
| 19303 | 1173 actually needed. A recommended mechanism: |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1174 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1175 1. In the plugin define user commands, functions and/or mappings that refer to |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1176 an autoload script. > |
| 23666 | 1177 command -nargs=1 SearchForStuff searchfor#Stuff(<f-args>) |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1178 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1179 < This goes in .../plugin/anyname.vim. "anyname.vim" can be freely chosen. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1180 |
| 21825 | 1181 2. In the autoload script do the actual work. You can import items from |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1182 other files to split up functionality in appropriate pieces. > |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1183 vim9script |
| 23573 | 1184 import FilterFunc from "../import/someother.vim" |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1185 def searchfor#Stuff(arg: string) |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1186 var filtered = FilterFunc(arg) |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1187 ... |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1188 < This goes in .../autoload/searchfor.vim. "searchfor" in the file name |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1189 must be exactly the same as the prefix for the function name, that is how |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1190 Vim finds the file. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1191 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1192 3. Other functionality, possibly shared between plugins, contains the exported |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1193 items and any private items. > |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1194 vim9script |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1195 var localVar = 'local' |
| 22171 | 1196 export def FilterFunc(arg: string): string |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1197 ... |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1198 < This goes in .../import/someother.vim. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1199 |
|
21771
fcf978444298
patch 8.2.1435: Vim9: always converting to string for ".." leads to mistakes
Bram Moolenaar <Bram@vim.org>
parents:
21717
diff
changeset
|
1200 When compiling a `:def` function and a function in an autoload script is |
|
fcf978444298
patch 8.2.1435: Vim9: always converting to string for ".." leads to mistakes
Bram Moolenaar <Bram@vim.org>
parents:
21717
diff
changeset
|
1201 encountered, the script is not loaded until the `:def` function is called. |
|
fcf978444298
patch 8.2.1435: Vim9: always converting to string for ".." leads to mistakes
Bram Moolenaar <Bram@vim.org>
parents:
21717
diff
changeset
|
1202 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1203 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1204 Import in legacy Vim script ~ |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1205 |
| 20856 | 1206 If an `import` statement is used in legacy Vim script, the script-local "s:" |
| 1207 namespace will be used for the imported item, even when "s:" is not specified. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1208 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1209 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1210 ============================================================================== |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1211 |
| 22328 | 1212 6. Future work: classes *vim9-classes* |
| 1213 | |
| 1214 Above "class" was mentioned a few times, but it has not been implemented yet. | |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1215 Most of Vim9 script can be created without this functionality, and since |
| 22328 | 1216 implementing classes is going to be a lot of work, it is left for the future. |
| 1217 For now we'll just make sure classes can be added later. | |
| 1218 | |
| 1219 Thoughts: | |
| 1220 - `class` / `endclass`, everything in one file | |
| 1221 - Class names are always CamelCase | |
| 1222 - Single constructor | |
| 1223 - Single inheritance with `class ThisClass extends BaseClass` | |
| 1224 - `abstract class` | |
| 1225 - `interface` (Abstract class without any implementation) | |
| 1226 - `class SomeClass implements SomeInterface` | |
| 1227 - Generics for class: `class <Tkey, Tentry>` | |
| 1228 - Generics for function: `def <Tkey> GetLast(key: Tkey)` | |
| 1229 | |
| 1230 Again, much of this is from TypeScript. | |
| 1231 | |
| 1232 Some things that look like good additions: | |
| 1233 - Use a class as an interface (like Dart) | |
| 1234 - Extend a class with methods, using an import (like Dart) | |
| 1235 | |
| 1236 An important class that will be provided is "Promise". Since Vim is single | |
| 1237 threaded, connecting asynchronous operations is a natural way of allowing | |
| 1238 plugins to do their work without blocking the user. It's a uniform way to | |
| 1239 invoke callbacks and handle timeouts and errors. | |
| 1240 | |
| 1241 ============================================================================== | |
| 1242 | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1243 9. Rationale *vim9-rationale* |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1244 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1245 The :def command ~ |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1246 |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1247 Plugin writers have asked for much faster Vim script. Investigations have |
| 19303 | 1248 shown that keeping the existing semantics of function calls make this close to |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1249 impossible, because of the overhead involved with calling a function, setting |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1250 up the local function scope and executing lines. There are many details that |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1251 need to be handled, such as error messages and exceptions. The need to create |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1252 a dictionary for a: and l: scopes, the a:000 list and several others add too |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1253 much overhead that cannot be avoided. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1254 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1255 Therefore the `:def` method to define a new-style function had to be added, |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1256 which allows for a function with different semantics. Most things still work |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1257 as before, but some parts do not. A new way to define a function was |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1258 considered the best way to separate the legacy style code from Vim9 style code. |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1259 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1260 Using "def" to define a function comes from Python. Other languages use |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1261 "function" which clashes with legacy Vim script. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1262 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1263 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1264 Type checking ~ |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1265 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1266 When compiling lines of Vim commands into instructions as much as possible |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1267 should be done at compile time. Postponing it to runtime makes the execution |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1268 slower and means mistakes are found only later. For example, when |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1269 encountering the "+" character and compiling this into a generic add |
| 23666 | 1270 instruction, at runtime the instruction would have to inspect the type of the |
| 1271 arguments and decide what kind of addition to do. And when the type is | |
| 1272 dictionary throw an error. If the types are known to be numbers then an "add | |
| 1273 number" instruction can be used, which is faster. The error can be given at | |
| 1274 compile time, no error handling is needed at runtime, since adding two numbers | |
| 1275 cannot fail. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1276 |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1277 The syntax for types, using <type> for compound types, is similar to Java. It |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1278 is easy to understand and widely used. The type names are what were used in |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1279 Vim before, with some additions such as "void" and "bool". |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1280 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1281 |
| 22328 | 1282 Removing clutter and weirdness ~ |
| 20856 | 1283 |
| 22328 | 1284 Once decided that `:def` functions have different syntax than legacy functions, |
| 1285 we are free to add improvements to make the code more familiar for users who | |
| 1286 know popular programming languages. In other words: remove weird things that | |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1287 only Vim does. |
| 22328 | 1288 |
| 1289 We can also remove clutter, mainly things that were done to make Vim script | |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1290 backwards compatible with the good old Vi commands. |
| 20856 | 1291 |
| 22328 | 1292 Examples: |
| 1293 - Drop `:call` for calling a function and `:eval` for manipulating data. | |
| 1294 - Drop using a leading backslash for line continuation, automatically figure | |
| 1295 out where an expression ends. | |
| 20856 | 1296 |
| 22328 | 1297 However, this does require that some things need to change: |
| 1298 - Comments start with # instead of ", to avoid confusing them with strings. | |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1299 This is good anyway, it is known from several popular languages. |
| 22328 | 1300 - Ex command ranges need to be prefixed with a colon, to avoid confusion with |
| 1301 expressions (single quote can be a string or a mark, "/" can be divide or a | |
| 1302 search command, etc.). | |
| 1303 | |
| 1304 Goal is to limit the differences. A good criteria is that when the old syntax | |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1305 is accidentally used you are very likely to get an error message. |
| 20856 | 1306 |
| 1307 | |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1308 Syntax and semantics from popular languages ~ |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1309 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1310 Script writers have complained that the Vim script syntax is unexpectedly |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1311 different from what they are used to. To reduce this complaint popular |
| 20856 | 1312 languages are used as an example. At the same time, we do not want to abandon |
| 1313 the well-known parts of legacy Vim script. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1314 |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1315 For many things TypeScript is followed. It's a recent language that is |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1316 gaining popularity and has similarities with Vim script. It also has a |
| 22328 | 1317 mix of static typing (a variable always has a known value type) and dynamic |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1318 typing (a variable can have different types, this changes at runtime). Since |
| 22328 | 1319 legacy Vim script is dynamically typed and a lot of existing functionality |
| 1320 (esp. builtin functions) depends on that, while static typing allows for much | |
| 1321 faster execution, we need to have this mix in Vim9 script. | |
| 1322 | |
| 22171 | 1323 There is no intention to completely match TypeScript syntax and semantics. We |
| 1324 just want to take those parts that we can use for Vim and we expect Vim users | |
| 22328 | 1325 will be happy with. TypeScript is a complex language with its own history, |
| 1326 advantages and disadvantages. To get an idea of the disadvantages read the | |
| 1327 book: "JavaScript: The Good Parts". Or find the article "TypeScript: the good | |
|
22272
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1328 parts" and read the "Things to avoid" section. |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1329 |
| 22328 | 1330 People familiar with other languages (Java, Python, etc.) will also find |
| 1331 things in TypeScript that they do not like or do not understand. We'll try to | |
| 1332 avoid those things. | |
|
22272
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1333 |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1334 Specific items from TypeScript we avoid: |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1335 - Overloading "+", using it both for addition and string concatenation. This |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1336 goes against legacy Vim script and often leads to mistakes. For that reason |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1337 we will keep using ".." for string concatenation. Lua also uses ".." this |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1338 way. And it allows for conversion to string for more values. |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1339 - TypeScript can use an expression like "99 || 'yes'" in a condition, but |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1340 cannot assign the value to a boolean. That is inconsistent and can be |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1341 annoying. Vim recognizes an expression with && or || and allows using the |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1342 result as a bool. TODO: to be reconsidered |
|
22272
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1343 - TypeScript considers an empty string as Falsy, but an empty list or dict as |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1344 Truthy. That is inconsistent. In Vim an empty list and dict are also |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1345 Falsy. |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1346 - TypeScript has various "Readonly" types, which have limited usefulness, |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1347 since a type cast can remove the immutable nature. Vim locks the value, |
|
eb1f5f618c75
patch 8.2.1685: Vim9: cannot declare a constant value
Bram Moolenaar <Bram@vim.org>
parents:
22171
diff
changeset
|
1348 which is more flexible, but is only checked at runtime. |
| 22171 | 1349 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1350 |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1351 Declarations ~ |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1352 |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1353 Legacy Vim script uses `:let` for every assignment, while in Vim9 declarations |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1354 are used. That is different, thus it's good to use a different command: |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1355 `:var`. This is used in many languages. The semantics might be slightly |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1356 different, but it's easily recognized as a declaration. |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1357 |
| 23047 | 1358 Using `:const` for constants is common, but the semantics varies. Some |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1359 languages only make the variable immutable, others also make the value |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1360 immutable. Since "final" is well known from Java for only making the variable |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1361 immutable we decided to use that. And then `:const` can be used for making |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1362 both immutable. This was also used in legacy Vim script and the meaning is |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1363 almost the same. |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1364 |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1365 What we end up with is very similar to Dart: > |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1366 :var name # mutable variable and value |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1367 :final name # immutable variable, mutable value |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1368 :const name # immutable variable and value |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1369 |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1370 Since legacy and Vim9 script will be mixed and global variables will be |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1371 shared, optional type checking is desirable. Also, type inference will avoid |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1372 the need for specifying the type in many cases. The TypeScript syntax fits |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1373 best for adding types to declarations: > |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1374 var name: string # string type is specified |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1375 ... |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1376 name = 'John' |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1377 const greeting = 'hello' # string type is inferred |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1378 |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1379 This is how we put types in a declaration: > |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1380 var mylist: list<string> |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1381 final mylist: list<string> = ['foo'] |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1382 def Func(arg1: number, arg2: string): bool |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1383 |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1384 Two alternatives were considered: |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1385 1. Put the type before the name, like Dart: > |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1386 var list<string> mylist |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1387 final list<string> mylist = ['foo'] |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1388 def Func(number arg1, string arg2) bool |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1389 2. Put the type after the variable name, but do not use a colon, like Go: > |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1390 var mylist list<string> |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1391 final mylist list<string> = ['foo'] |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1392 def Func(arg1 number, arg2 string) bool |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1393 |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1394 The first is more familiar for anyone used to C or Java. The second one |
| 22565 | 1395 doesn't really have an advantage over the first, so let's discard the second. |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1396 |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1397 Since we use type inference the type can be left out when it can be inferred |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1398 from the value. This means that after `var` we don't know if a type or a name |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1399 follows. That makes parsing harder, not only for Vim but also for humans. |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1400 Also, it will not be allowed to use a variable name that could be a type name, |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1401 using `var string string` is too confusing. |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1402 |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1403 The chosen syntax, using a colon to separate the name from the type, adds |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1404 punctuation, but it actually makes it easier to recognize the parts of a |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1405 declaration. |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1406 |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1407 |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1408 Expressions ~ |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1409 |
| 22565 | 1410 Expression evaluation was already close to what other languages are doing. |
| 1411 Some details are unexpected and can be improved. For example a boolean | |
| 1412 condition would accept a string, convert it to a number and check if the | |
| 1413 number is non-zero. This is unexpected and often leads to mistakes, since | |
| 1414 text not starting with a number would be converted to zero, which is | |
| 22723 | 1415 considered false. Thus using a string for a condition would often not give an |
| 1416 error and be considered false. That is confusing. | |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1417 |
| 23047 | 1418 In Vim9 type checking is stricter to avoid mistakes. Where a condition is |
| 22565 | 1419 used, e.g. with the `:if` command and the `||` operator, only boolean-like |
| 1420 values are accepted: | |
| 1421 true: `true`, `v:true`, `1`, `0 < 9` | |
| 1422 false: `false`, `v:false`, `0`, `0 > 9` | |
| 1423 Note that the number zero is false and the number one is true. This is more | |
| 22723 | 1424 permissive than most other languages. It was done because many builtin |
| 22565 | 1425 functions return these values. |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1426 |
| 22565 | 1427 If you have any type of value and want to use it as a boolean, use the `!!` |
| 1428 operator: | |
| 1429 true: !`!'text'`, `!![99]`, `!!{'x': 1}`, `!!99` | |
| 1430 false: `!!''`, `!![]`, `!!{}` | |
| 1431 | |
| 1432 From a language like JavaScript we have this handy construct: > | |
| 1433 GetName() || 'unknown' | |
| 1434 However, this conflicts with only allowing a boolean for a condition. | |
| 1435 Therefore the "??" operator was added: > | |
| 1436 GetName() ?? 'unknown' | |
| 1437 Here you can explicitly express your intention to use the value as-is and not | |
| 1438 result in a boolean. This is called the |falsy-operator|. | |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1439 |
|
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1440 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1441 Import and Export ~ |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1442 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1443 A problem of legacy Vim script is that by default all functions and variables |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1444 are global. It is possible to make them script-local, but then they are not |
| 22171 | 1445 available in other scripts. This defies the concept of a package that only |
| 1446 exports selected items and keeps the rest local. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1447 |
| 21825 | 1448 In Vim9 script a mechanism very similar to the JavaScript import and export |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1449 mechanism is supported. It is a variant to the existing `:source` command |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1450 that works like one would expect: |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1451 - Instead of making everything global by default, everything is script-local, |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1452 unless exported. |
| 22171 | 1453 - When importing a script the symbols that are imported are explicitly listed, |
| 1454 avoiding name conflicts and failures if functionality is added later. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1455 - The mechanism allows for writing a big, long script with a very clear API: |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1456 the exported function(s) and class(es). |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1457 - By using relative paths loading can be much faster for an import inside of a |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1458 package, no need to search many directories. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1459 - Once an import has been used, it can be cached and loading it again can be |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1460 avoided. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1461 - The Vim-specific use of "s:" to make things script-local can be dropped. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1462 |
| 20856 | 1463 When sourcing a Vim9 script from a legacy script, only the items defined |
| 1464 globally can be used, not the exported items. Alternatives considered: | |
| 1465 - All the exported items become available as script-local items. This makes | |
| 22171 | 1466 it uncontrollable what items get defined and likely soon leads to trouble. |
| 20856 | 1467 - Use the exported items and make them global. Disadvantage is that it's then |
| 1468 not possible to avoid name clashes in the global namespace. | |
| 1469 - Completely disallow sourcing a Vim9 script, require using `:import`. That | |
| 1470 makes it difficult to use scripts for testing, or sourcing them from the | |
| 1471 command line to try them out. | |
| 22171 | 1472 Note that you can also use `:import` in legacy Vim script, see above. |
| 20856 | 1473 |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1474 |
| 22328 | 1475 Compiling functions early ~ |
| 1476 | |
| 1477 Functions are compiled when called or when `:defcompile` is used. Why not | |
| 1478 compile them early, so that syntax and type errors are reported early? | |
| 1479 | |
| 1480 The functions can't be compiled right away when encountered, because there may | |
| 1481 be forward references to functions defined later. Consider defining functions | |
| 1482 A, B and C, where A calls B, B calls C, and C calls A again. It's impossible | |
| 1483 to reorder the functions to avoid forward references. | |
| 1484 | |
| 1485 An alternative would be to first scan through the file to locate items and | |
| 1486 figure out their type, so that forward references are found, and only then | |
| 1487 execute the script and compile the functions. This means the script has to be | |
| 1488 parsed twice, which is slower, and some conditions at the script level, such | |
| 1489 as checking if a feature is supported, are hard to use. An attempt was made | |
| 1490 to see if it works, but it turned out to be impossible to make work nicely. | |
| 1491 | |
| 1492 It would be possible to compile all the functions at the end of the script. | |
| 1493 The drawback is that if a function never gets called, the overhead of | |
| 1494 compiling it counts anyway. Since startup speed is very important, in most | |
| 1495 cases it's better to do it later and accept that syntax and type errors are | |
| 1496 only reported then. In case these errors should be found early, e.g. when | |
| 1497 testing, the `:defcompile` command will help out. | |
| 1498 | |
| 1499 | |
|
22391
a9fb7efa31d6
patch 8.2.1744: Vim9: using ":const!" is weird
Bram Moolenaar <Bram@vim.org>
parents:
22328
diff
changeset
|
1500 Why not use an embedded language? ~ |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1501 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1502 Vim supports interfaces to Perl, Python, Lua, Tcl and a few others. But |
| 22328 | 1503 these interfaces have never become widely used, for various reasons. When |
| 1504 Vim9 was designed a decision was made to make these interfaces lower priority | |
| 1505 and concentrate on Vim script. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1506 |
| 22328 | 1507 Still, plugin writers may find other languages more familiar, want to use |
| 1508 existing libraries or see a performance benefit. We encourage plugin authors | |
| 1509 to write code in any language and run it as an external tool, using jobs and | |
| 1510 channels. We can try to make this easier somehow. | |
| 1511 | |
| 1512 Using an external tool also has disadvantages. An alternative is to convert | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1513 the tool into Vim script. For that to be possible without too much |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1514 translation, and keeping the code fast at the same time, the constructs of the |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1515 tool need to be supported. Since most languages support classes the lack of |
| 22171 | 1516 support for classes in Vim is then a problem. |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1517 |
| 22328 | 1518 |
| 1519 Classes ~ | |
| 1520 | |
| 1521 Vim supports a kind-of object oriented programming by adding methods to a | |
| 1522 dictionary. With some care this can be made to work, but it does not look | |
| 1523 like real classes. On top of that, it's quite slow, because of the use of | |
| 1524 dictionaries. | |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1525 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1526 The support of classes in Vim9 script is a "minimal common functionality" of |
| 22171 | 1527 class support in most languages. It works much like Java, which is the most |
|
19181
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1528 popular programming language. |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1529 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1530 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1531 |
|
94eda51ba9ba
patch 8.2.0149: maintaining a Vim9 branch separately is more work
Bram Moolenaar <Bram@vim.org>
parents:
diff
changeset
|
1532 vim:tw=78:ts=8:noet:ft=help:norl: |