patch 8.2.2760: Vim9: no error for changing a for loop variable Commit: https://github.com/vim/vim/commit/f6a8d420a8d2924737f713de046947dcb487550c Author: Bram Moolenaar <Bram@vim.org> Date: Tue Apr 13 21:48:03 2021 +0200 patch 8.2.2760: Vim9: no error for changing a for loop variable Problem: Vim9: no error for changing a for loop variable. Solution: Make the loop variable read-only. (issue https://github.com/vim/vim/issues/8102)

--- a/src/vim.h
+++ b/src/vim.h
@@ -2158,6 +2158,7 @@ typedef enum {
 #define ASSIGN_DECL	0x08  // may declare variable if it does not exist
 #define ASSIGN_UNPACK	0x10  // using [a, b] = list
 #define ASSIGN_NO_MEMBER_TYPE 0x20 // use "any" for list and dict member type
+#define ASSIGN_FOR_LOOP 0x40 // assigning to loop variable
 
 #include "ex_cmds.h"	    // Ex command defines
 #include "spell.h"	    // spell checking stuff