patch 8.2.1924: Vim9: crash when indexing dict with NULL key Commit: https://github.com/vim/vim/commit/086fc9a585afa4317046fa0a36c7b896286e5128 Author: Bram Moolenaar <Bram@vim.org> Date: Fri Oct 30 18:33:02 2020 +0100 patch 8.2.1924: Vim9: crash when indexing dict with NULL key Problem: Vim9: crash when indexing dict with NULL key. Solution: Use empty string instead of NULL. (closes https://github.com/vim/vim/issues/7229) Make error message more useful for empty string.