Mercurial > vim
annotate runtime/doc/usr_29.txt @ 2287:573da4dac306 vim73
Make the dos installer work with more compilers.
author | Bram Moolenaar <bram@vim.org> |
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date | Wed, 07 Jul 2010 15:14:03 +0200 |
parents | 7c8c7c95a865 |
children | 733f0dc510c3 12b829477c60 |
rev | line source |
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2154
7c8c7c95a865
First step in the Vim 7.3 branch. Changed version numbers.
Bram Moolenaar <bram@zimbu.org>
parents:
1702
diff
changeset
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1 *usr_29.txt* For Vim version 7.3a. Last change: 2008 Jun 28 |
7 | 2 |
3 VIM USER MANUAL - by Bram Moolenaar | |
4 | |
5 Moving through programs | |
6 | |
7 | |
8 The creator of Vim is a computer programmer. It's no surprise that Vim | |
9 contains many features to aid in writing programs. Jump around to find where | |
10 identifiers are defined and used. Preview declarations in a separate window. | |
11 There is more in the next chapter. | |
12 | |
13 |29.1| Using tags | |
14 |29.2| The preview window | |
15 |29.3| Moving through a program | |
16 |29.4| Finding global identifiers | |
17 |29.5| Finding local identifiers | |
18 | |
19 Next chapter: |usr_30.txt| Editing programs | |
20 Previous chapter: |usr_28.txt| Folding | |
21 Table of contents: |usr_toc.txt| | |
22 | |
23 ============================================================================== | |
24 *29.1* Using tags | |
25 | |
26 What is a tag? It is a location where an identifier is defined. An example | |
27 is a function definition in a C or C++ program. A list of tags is kept in a | |
28 tags file. This can be used by Vim to directly jump from any place to the | |
29 tag, the place where an identifier is defined. | |
30 To generate the tags file for all C files in the current directory, use the | |
31 following command: > | |
32 | |
33 ctags *.c | |
34 | |
35 "ctags" is a separate program. Most Unix systems already have it installed. | |
36 If you do not have it yet, you can find Exuberant ctags here: | |
37 | |
38 http://ctags.sf.net ~ | |
39 | |
40 Now when you are in Vim and you want to go to a function definition, you can | |
41 jump to it by using the following command: > | |
42 | |
43 :tag startlist | |
44 | |
45 This command will find the function "startlist" even if it is in another file. | |
46 The CTRL-] command jumps to the tag of the word that is under the cursor. | |
47 This makes it easy to explore a tangle of C code. Suppose, for example, that | |
48 you are in the function "write_block". You can see that it calls | |
49 "write_line". But what does "write_line" do? By placing the cursor on the | |
50 call to "write_line" and pressing CTRL-], you jump to the definition of this | |
51 function. | |
52 The "write_line" function calls "write_char". You need to figure out what | |
53 it does. So you position the cursor over the call to "write_char" and press | |
54 CTRL-]. Now you are at the definition of "write_char". | |
55 | |
56 +-------------------------------------+ | |
57 |void write_block(char **s; int cnt) | | |
58 |{ | | |
59 | int i; | | |
60 | for (i = 0; i < cnt; ++i) | | |
61 | write_line(s[i]); | | |
62 |} | | | |
63 +-----------|-------------------------+ | |
64 | | |
65 CTRL-] | | |
66 | +----------------------------+ | |
67 +--> |void write_line(char *s) | | |
68 |{ | | |
69 | while (*s != 0) | | |
70 | write_char(*s++); | | |
71 |} | | | |
72 +--------|-------------------+ | |
73 | | |
74 CTRL-] | | |
75 | +------------------------------------+ | |
76 +--> |void write_char(char c) | | |
77 |{ | | |
78 | putchar((int)(unsigned char)c); | | |
79 |} | | |
80 +------------------------------------+ | |
81 | |
82 The ":tags" command shows the list of tags that you traversed through: | |
83 | |
84 :tags | |
85 # TO tag FROM line in file/text ~ | |
86 1 1 write_line 8 write_block.c ~ | |
87 2 1 write_char 7 write_line.c ~ | |
88 > ~ | |
89 > | |
90 Now to go back. The CTRL-T command goes to the preceding tag. In the example | |
91 above you get back to the "write_line" function, in the call to "write_char". | |
92 This command takes a count argument that indicates how many tags to jump | |
93 back. You have gone forward, and now back. Let's go forward again. The | |
94 following command goes to the tag on top of the list: > | |
95 | |
96 :tag | |
97 | |
98 You can prefix it with a count and jump forward that many tags. For example: | |
99 ":3tag". CTRL-T also can be preceded with a count. | |
100 These commands thus allow you to go down a call tree with CTRL-] and back | |
101 up again with CTRL-T. Use ":tags" to find out where you are. | |
102 | |
103 | |
104 SPLIT WINDOWS | |
105 | |
106 The ":tag" command replaces the file in the current window with the one | |
107 containing the new function. But suppose you want to see not only the old | |
108 function but also the new one? You can split the window using the ":split" | |
109 command followed by the ":tag" command. Vim has a shorthand command that does | |
110 both: > | |
111 :stag tagname | |
112 | |
113 To split the current window and jump to the tag under the cursor use this | |
114 command: > | |
115 | |
116 CTRL-W ] | |
117 | |
118 If a count is specified, the new window will be that many lines high. | |
119 | |
120 | |
121 MORE TAGS FILES | |
122 | |
123 When you have files in many directories, you can create a tags file in each of | |
124 them. Vim will then only be able to jump to tags within that directory. | |
125 To find more tags files, set the 'tags' option to include all the relevant | |
126 tags files. Example: > | |
127 | |
128 :set tags=./tags,./../tags,./*/tags | |
129 | |
130 This finds a tags file in the same directory as the current file, one | |
131 directory level higher and in all subdirectories. | |
132 This is quite a number of tags files, but it may still not be enough. For | |
133 example, when editing a file in "~/proj/src", you will not find the tags file | |
134 "~/proj/sub/tags". For this situation Vim offers to search a whole directory | |
135 tree for tags files. Example: > | |
136 | |
137 :set tags=~/proj/**/tags | |
138 | |
139 | |
140 ONE TAGS FILE | |
141 | |
142 When Vim has to search many places for tags files, you can hear the disk | |
143 rattling. It may get a bit slow. In that case it's better to spend this | |
144 time while generating one big tags file. You might do this overnight. | |
145 This requires the Exuberant ctags program, mentioned above. It offers an | |
146 argument to search a whole directory tree: > | |
147 | |
148 cd ~/proj | |
149 ctags -R . | |
150 | |
151 The nice thing about this is that Exuberant ctags recognizes various file | |
152 types. Thus this doesn't work just for C and C++ programs, also for Eiffel | |
153 and even Vim scripts. See the ctags documentation to tune this. | |
154 Now you only need to tell Vim where your big tags file is: > | |
155 | |
156 :set tags=~/proj/tags | |
157 | |
158 | |
159 MULTIPLE MATCHES | |
160 | |
161 When a function is defined multiple times (or a method in several classes), | |
162 the ":tag" command will jump to the first one. If there is a match in the | |
163 current file, that one is used first. | |
164 You can now jump to other matches for the same tag with: > | |
165 | |
166 :tnext | |
167 | |
168 Repeat this to find further matches. If there are many, you can select which | |
169 one to jump to: > | |
170 | |
171 :tselect tagname | |
172 | |
173 Vim will present you with a list of choices: | |
174 | |
175 # pri kind tag file ~ | |
176 1 F f mch_init os_amiga.c ~ | |
177 mch_init() ~ | |
178 2 F f mch_init os_mac.c ~ | |
179 mch_init() ~ | |
180 3 F f mch_init os_msdos.c ~ | |
181 mch_init(void) ~ | |
182 4 F f mch_init os_riscos.c ~ | |
183 mch_init() ~ | |
184 Enter nr of choice (<CR> to abort): ~ | |
185 | |
186 You can now enter the number (in the first column) of the match that you would | |
187 like to jump to. The information in the other columns give you a good idea of | |
188 where the match is defined. | |
189 | |
190 To move between the matching tags, these commands can be used: | |
191 | |
192 :tfirst go to first match | |
193 :[count]tprevious go to [count] previous match | |
194 :[count]tnext go to [count] next match | |
195 :tlast go to last match | |
196 | |
197 If [count] is omitted then one is used. | |
198 | |
199 | |
200 GUESSING TAG NAMES | |
201 | |
202 Command line completion is a good way to avoid typing a long tag name. Just | |
203 type the first bit and press <Tab>: > | |
204 | |
205 :tag write_<Tab> | |
206 | |
207 You will get the first match. If it's not the one you want, press <Tab> until | |
208 you find the right one. | |
209 Sometimes you only know part of the name of a function. Or you have many | |
210 tags that start with the same string, but end differently. Then you can tell | |
211 Vim to use a pattern to find the tag. | |
212 Suppose you want to jump to a tag that contains "block". First type | |
213 this: > | |
214 | |
215 :tag /block | |
216 | |
217 Now use command line completion: press <Tab>. Vim will find all tags that | |
218 contain "block" and use the first match. | |
219 The "/" before a tag name tells Vim that what follows is not a literal tag | |
220 name, but a pattern. You can use all the items for search patterns here. For | |
221 example, suppose you want to select a tag that starts with "write_": > | |
222 | |
223 :tselect /^write_ | |
224 | |
225 The "^" specifies that the tag starts with "write_". Otherwise it would also | |
226 be found halfway a tag name. Similarly "$" at the end makes sure the pattern | |
227 matches until the end of a tag. | |
228 | |
229 | |
230 A TAGS BROWSER | |
231 | |
232 Since CTRL-] takes you to the definition of the identifier under the cursor, | |
233 you can use a list of identifier names as a table of contents. Here is an | |
234 example. | |
235 First create a list of identifiers (this requires Exuberant ctags): > | |
236 | |
237 ctags --c-types=f -f functions *.c | |
238 | |
239 Now start Vim without a file, and edit this file in Vim, in a vertically split | |
240 window: > | |
241 | |
242 vim | |
243 :vsplit functions | |
244 | |
245 The window contains a list of all the functions. There is some more stuff, | |
246 but you can ignore that. Do ":setlocal ts=99" to clean it up a bit. | |
247 In this window, define a mapping: > | |
248 | |
249 :nnoremap <buffer> <CR> 0ye<C-W>w:tag <C-R>"<CR> | |
250 | |
251 Move the cursor to the line that contains the function you want to go to. | |
252 Now press <Enter>. Vim will go to the other window and jump to the selected | |
253 function. | |
254 | |
255 | |
256 RELATED ITEMS | |
257 | |
258 You can set 'ignorecase' to make case in tag names be ignored. | |
259 | |
260 The 'tagbsearch' option tells if the tags file is sorted or not. The default | |
261 is to assume a sorted tags file, which makes a tags search a lot faster, but | |
262 doesn't work if the tags file isn't sorted. | |
263 | |
264 The 'taglength' option can be used to tell Vim the number of significant | |
265 characters in a tag. | |
266 | |
267 When you use the SNiFF+ program, you can use the Vim interface to it |sniff|. | |
268 SNiFF+ is a commercial program. | |
269 | |
270 Cscope is a free program. It does not only find places where an identifier is | |
271 declared, but also where it is used. See |cscope|. | |
272 | |
273 ============================================================================== | |
274 *29.2* The preview window | |
275 | |
276 When you edit code that contains a function call, you need to use the correct | |
277 arguments. To know what values to pass you can look at how the function is | |
278 defined. The tags mechanism works very well for this. Preferably the | |
279 definition is displayed in another window. For this the preview window can be | |
280 used. | |
281 To open a preview window to display the function "write_char": > | |
282 | |
283 :ptag write_char | |
284 | |
285 Vim will open a window, and jumps to the tag "write_char". Then it takes you | |
286 back to the original position. Thus you can continue typing without the need | |
287 to use a CTRL-W command. | |
288 If the name of a function appears in the text, you can get its definition | |
289 in the preview window with: > | |
290 | |
291 CTRL-W } | |
292 | |
293 There is a script that automatically displays the text where the word under | |
294 the cursor was defined. See |CursorHold-example|. | |
295 | |
296 To close the preview window use this command: > | |
297 | |
298 :pclose | |
299 | |
300 To edit a specific file in the preview window, use ":pedit". This can be | |
301 useful to edit a header file, for example: > | |
302 | |
303 :pedit defs.h | |
304 | |
305 Finally, ":psearch" can be used to find a word in the current file and any | |
306 included files and display the match in the preview window. This is | |
307 especially useful when using library functions, for which you do not have a | |
308 tags file. Example: > | |
309 | |
310 :psearch popen | |
311 | |
312 This will show the "stdio.h" file in the preview window, with the function | |
313 prototype for popen(): | |
314 | |
315 FILE *popen __P((const char *, const char *)); ~ | |
316 | |
317 You can specify the height of the preview window, when it is opened, with the | |
318 'previewheight' option. | |
319 | |
320 ============================================================================== | |
321 *29.3* Moving through a program | |
322 | |
323 Since a program is structured, Vim can recognize items in it. Specific | |
324 commands can be used to move around. | |
325 C programs often contain constructs like this: | |
326 | |
327 #ifdef USE_POPEN ~ | |
328 fd = popen("ls", "r") ~ | |
329 #else ~ | |
330 fd = fopen("tmp", "w") ~ | |
331 #endif ~ | |
332 | |
333 But then much longer, and possibly nested. Position the cursor on the | |
334 "#ifdef" and press %. Vim will jump to the "#else". Pressing % again takes | |
335 you to the "#endif". Another % takes you to the "#ifdef" again. | |
336 When the construct is nested, Vim will find the matching items. This is a | |
337 good way to check if you didn't forget an "#endif". | |
338 When you are somewhere inside a "#if" - "#endif", you can jump to the start | |
339 of it with: > | |
340 | |
341 [# | |
342 | |
343 If you are not after a "#if" or "#ifdef" Vim will beep. To jump forward to | |
344 the next "#else" or "#endif" use: > | |
345 | |
346 ]# | |
347 | |
348 These two commands skip any "#if" - "#endif" blocks that they encounter. | |
349 Example: | |
350 | |
351 #if defined(HAS_INC_H) ~ | |
352 a = a + inc(); ~ | |
353 # ifdef USE_THEME ~ | |
354 a += 3; ~ | |
355 # endif ~ | |
356 set_width(a); ~ | |
357 | |
358 With the cursor in the last line, "[#" moves to the first line. The "#ifdef" | |
359 - "#endif" block in the middle is skipped. | |
360 | |
361 | |
362 MOVING IN CODE BLOCKS | |
363 | |
364 In C code blocks are enclosed in {}. These can get pretty long. To move to | |
365 the start of the outer block use the "[[" command. Use "][" to find the end. | |
366 This assumes that the "{" and "}" are in the first column. | |
367 The "[{" command moves to the start of the current block. It skips over | |
368 pairs of {} at the same level. "]}" jumps to the end. | |
369 An overview: | |
370 | |
371 function(int a) | |
372 +-> { | |
373 | if (a) | |
374 | +-> { | |
375 [[ | | for (;;) --+ | |
376 | | +-> { | | |
377 | [{ | | foo(32); | --+ | |
378 | | [{ | if (bar(a)) --+ | ]} | | |
379 +-- | +-- break; | ]} | | | |
380 | } <-+ | | ][ | |
381 +-- foobar(a) | | | |
382 } <-+ | | |
383 } <-+ | |
384 | |
385 When writing C++ or Java, the outer {} block is for the class. The next level | |
386 of {} is for a method. When somewhere inside a class use "[m" to find the | |
1621 | 387 previous start of a method. "]m" finds the next start of a method. |
7 | 388 |
389 Additionally, "[]" moves backward to the end of a function and "]]" moves | |
390 forward to the start of the next function. The end of a function is defined | |
391 by a "}" in the first column. | |
392 | |
393 int func1(void) | |
394 { | |
395 return 1; | |
396 +----------> } | |
397 | | |
398 [] | int func2(void) | |
399 | +-> { | |
400 | [[ | if (flag) | |
401 start +-- +-- return flag; | |
402 | ][ | return 2; | |
403 | +-> } | |
404 ]] | | |
405 | int func3(void) | |
406 +----------> { | |
407 return 3; | |
408 } | |
409 | |
410 Don't forget you can also use "%" to move between matching (), {} and []. | |
411 That also works when they are many lines apart. | |
412 | |
413 | |
414 MOVING IN BRACES | |
415 | |
416 The "[(" and "])" commands work similar to "[{" and "]}", except that they | |
417 work on () pairs instead of {} pairs. | |
418 > | |
419 [( | |
420 < <-------------------------------- | |
421 <------- | |
422 if (a == b && (c == d || (e > f)) && x > y) ~ | |
423 --------------> | |
424 --------------------------------> > | |
425 ]) | |
426 | |
427 MOVING IN COMMENTS | |
428 | |
429 To move back to the start of a comment use "[/". Move forward to the end of a | |
430 comment with "]/". This only works for /* - */ comments. | |
431 | |
432 +-> +-> /* | |
433 | [/ | * A comment about --+ | |
434 [/ | +-- * wonderful life. | ]/ | |
435 | */ <-+ | |
436 | | |
437 +-- foo = bar * 3; --+ | |
438 | ]/ | |
439 /* a short comment */ <-+ | |
440 | |
441 ============================================================================== | |
442 *29.4* Finding global identifiers | |
443 | |
444 You are editing a C program and wonder if a variable is declared as "int" or | |
445 "unsigned". A quick way to find this is with the "[I" command. | |
446 Suppose the cursor is on the word "column". Type: > | |
447 | |
448 [I | |
449 | |
450 Vim will list the matching lines it can find. Not only in the current file, | |
451 but also in all included files (and files included in them, etc.). The result | |
452 looks like this: | |
453 | |
454 structs.h ~ | |
455 1: 29 unsigned column; /* column number */ ~ | |
456 | |
457 The advantage over using tags or the preview window is that included files are | |
458 searched. In most cases this results in the right declaration to be found. | |
459 Also when the tags file is out of date. Also when you don't have tags for the | |
460 included files. | |
461 However, a few things must be right for "[I" to do its work. First of all, | |
462 the 'include' option must specify how a file is included. The default value | |
463 works for C and C++. For other languages you will have to change it. | |
464 | |
465 | |
466 LOCATING INCLUDED FILES | |
467 | |
468 Vim will find included files in the places specified with the 'path' | |
469 option. If a directory is missing, some include files will not be found. You | |
470 can discover this with this command: > | |
471 | |
472 :checkpath | |
473 | |
474 It will list the include files that could not be found. Also files included | |
475 by the files that could be found. An example of the output: | |
476 | |
477 --- Included files not found in path --- ~ | |
478 <io.h> ~ | |
479 vim.h --> ~ | |
480 <functions.h> ~ | |
481 <clib/exec_protos.h> ~ | |
482 | |
483 The "io.h" file is included by the current file and can't be found. "vim.h" | |
484 can be found, thus ":checkpath" goes into this file and checks what it | |
485 includes. The "functions.h" and "clib/exec_protos.h" files, included by | |
486 "vim.h" are not found. | |
487 | |
488 Note: | |
489 Vim is not a compiler. It does not recognize "#ifdef" statements. | |
490 This means every "#include" statement is used, also when it comes | |
491 after "#if NEVER". | |
492 | |
493 To fix the files that could not be found, add a directory to the 'path' | |
494 option. A good place to find out about this is the Makefile. Look out for | |
495 lines that contain "-I" items, like "-I/usr/local/X11". To add this directory | |
496 use: > | |
497 | |
498 :set path+=/usr/local/X11 | |
499 | |
1621 | 500 When there are many subdirectories, you can use the "*" wildcard. Example: > |
7 | 501 |
502 :set path+=/usr/*/include | |
503 | |
504 This would find files in "/usr/local/include" as well as "/usr/X11/include". | |
505 | |
506 When working on a project with a whole nested tree of included files, the "**" | |
507 items is useful. This will search down in all subdirectories. Example: > | |
508 | |
509 :set path+=/projects/invent/**/include | |
510 | |
511 This will find files in the directories: | |
512 | |
513 /projects/invent/include ~ | |
514 /projects/invent/main/include ~ | |
515 /projects/invent/main/os/include ~ | |
516 etc. | |
517 | |
518 There are even more possibilities. Check out the 'path' option for info. | |
519 If you want to see which included files are actually found, use this | |
520 command: > | |
521 | |
522 :checkpath! | |
523 | |
524 You will get a (very long) list of included files, the files they include, and | |
525 so on. To shorten the list a bit, Vim shows "(Already listed)" for files that | |
526 were found before and doesn't list the included files in there again. | |
527 | |
528 | |
529 JUMPING TO A MATCH | |
530 | |
531 "[I" produces a list with only one line of text. When you want to have a | |
532 closer look at the first item, you can jump to that line with the command: > | |
533 | |
534 [<Tab> | |
535 | |
536 You can also use "[ CTRL-I", since CTRL-I is the same as pressing <Tab>. | |
537 | |
538 The list that "[I" produces has a number at the start of each line. When you | |
539 want to jump to another item than the first one, type the number first: > | |
540 | |
541 3[<Tab> | |
542 | |
543 Will jump to the third item in the list. Remember that you can use CTRL-O to | |
544 jump back to where you started from. | |
545 | |
546 | |
547 RELATED COMMANDS | |
548 | |
549 [i only lists the first match | |
550 ]I only lists items below the cursor | |
551 ]i only lists the first item below the cursor | |
552 | |
553 | |
554 FINDING DEFINED IDENTIFIERS | |
555 | |
556 The "[I" command finds any identifier. To find only macros, defined with | |
557 "#define" use: > | |
558 | |
559 [D | |
560 | |
561 Again, this searches in included files. The 'define' option specifies what a | |
562 line looks like that defines the items for "[D". You could change it to make | |
563 it work with other languages than C or C++. | |
564 The commands related to "[D" are: | |
565 | |
566 [d only lists the first match | |
567 ]D only lists items below the cursor | |
568 ]d only lists the first item below the cursor | |
569 | |
570 ============================================================================== | |
571 *29.5* Finding local identifiers | |
572 | |
573 The "[I" command searches included files. To search in the current file only, | |
574 and jump to the first place where the word under the cursor is used: > | |
575 | |
576 gD | |
577 | |
578 Hint: Goto Definition. This command is very useful to find a variable or | |
579 function that was declared locally ("static", in C terms). Example (cursor on | |
580 "counter"): | |
581 | |
582 +-> static int counter = 0; | |
583 | | |
584 | int get_counter(void) | |
585 gD | { | |
586 | ++counter; | |
587 +-- return counter; | |
588 } | |
589 | |
590 To restrict the search even further, and look only in the current function, | |
591 use this command: > | |
592 | |
593 gd | |
594 | |
595 This will go back to the start of the current function and find the first | |
596 occurrence of the word under the cursor. Actually, it searches backwards to | |
1668 | 597 an empty line above a "{" in the first column. From there it searches forward |
598 for the identifier. Example (cursor on "idx"): | |
7 | 599 |
600 int find_entry(char *name) | |
601 { | |
602 +-> int idx; | |
603 | | |
604 gd | for (idx = 0; idx < table_len; ++idx) | |
605 | if (strcmp(table[idx].name, name) == 0) | |
606 +-- return idx; | |
607 } | |
608 | |
609 ============================================================================== | |
610 | |
611 Next chapter: |usr_30.txt| Editing programs | |
612 | |
613 Copyright: see |manual-copyright| vim:tw=78:ts=8:ft=help:norl: |