vim-patch:63d08d4: runtime(doc): update :h write-plugin and readdir() example

1) The complete example plugin at :h write-plugin the end of the
   documentation didn't reflect the snippets provided during the
   tutorial. In most of the Add() function, interpolated strings are
   used, but the final result used concatenated strings.

2) The example provided in readdir() to get a list of files ending in
   ".txt" didn't properly escape the dot in the regular expression:
      readdir(dirname, {n -> n =~ '.txt$'})
   This would match any file ending with "txt" that is at least 4
   characters long, instead it should be:
      readdir(dirname, {n -> n =~ '\.txt$'})

closes: vim/vim#21123

https://github.com/vim/vim/commit/63d08d43862ed195da78cfb1bebe2c0ed02f80b7

Co-authored-by: Josep Puigdemont <josep.puigdemont@gmail.com>

0 files changed, 0 insertions, 0 deletions