patch 8.2.4823: concat more than 2 strings in :def function is inefficient Commit: https://github.com/vim/vim/commit/372bcceeee8012ef3fb2f3dbc8132c3a33cb84fc Author: LemonBoy <thatlemon@gmail.com> Date: Mon Apr 25 12:43:20 2022 +0100 patch 8.2.4823: concat more than 2 strings in :def function is inefficient Problem: Concatenating more than 2 strings in a :def function is inefficient. Solution: Add a count to the CONCAT instruction. (closes #10276)

--- a/src/vim9.h
+++ b/src/vim9.h
@@ -152,7 +152,7 @@ typedef enum {
     ISN_COMPAREANY,
 
     // expression operations
-    ISN_CONCAT,
+    ISN_CONCAT,     // concatenate isn_arg.number strings
     ISN_STRINDEX,   // [expr] string index
     ISN_STRSLICE,   // [expr:expr] string slice
     ISN_LISTAPPEND, // append to a list, like add()