patch 8.0.1251: invalid expressin passed to WaitFor() commit https://github.com/vim/vim/commit/d97fbf171ec0e63117813da045d2a1c51a9b6f62 Author: Bram Moolenaar <Bram@vim.org> Date: Thu Nov 2 19:23:03 2017 +0100 patch 8.0.1251: invalid expressin passed to WaitFor() Problem: Invalid expressin passed to WaitFor(). Solution: Check if the variable exists.

" Vim filetype plugin file
" Language: 	tmux(1) configuration file
" URL: 		https://github.com/ericpruitt/tmux.vim/
" Maintainer: 	Eric Pruitt <eric.pruitt@gmail.com>
" Last Changed: 2017 Mar 10

if exists("b:did_ftplugin")
  finish
endif
let b:did_ftplugin = 1

setlocal commentstring=#\ %s