patch 8.2.3423: Vim9: list += list creates a new list in :def function Commit: https://github.com/vim/vim/commit/07802044b90b2cbcc64b2dfe235f019d7c37589c Author: Bram Moolenaar <Bram@vim.org> Date: Thu Sep 9 23:01:14 2021 +0200 patch 8.2.3423: Vim9: list += list creates a new list in :def function Problem: Vim9: list += list creates a new list in :def function. Solution: Append to the existing list.

/* bufwrite.c */
char *new_file_message(void);
int buf_write(buf_T *buf, char_u *fname, char_u *sfname, linenr_T start, linenr_T end, exarg_T *eap, int append, int forceit, int reset_changed, int filtering);
/* vim: set ft=c : */