patch 8.0.0649: when opening a help file the filetype is set several times commit https://github.com/vim/vim/commit/9049298f8d0bbc237b7c666c7ad6cdabe738e8fc Author: Bram Moolenaar <Bram@vim.org> Date: Thu Jun 22 14:16:31 2017 +0200 patch 8.0.0649: when opening a help file the filetype is set several times Problem: When opening a help file the filetype is set several times. Solution: When setting the filetype to the same value from a modeline, don't trigger FileType autocommands. Don't set the filetype to "help" when it's already set correctly.

" Vim compiler file
" Compiler:         GHC Haskell Compiler
" Maintainer:       Daniel Campoverde <alx@sillybytes.net>
" Latest Revision:  2016-11-29

if exists("current_compiler")
  finish
endif
let current_compiler = "ghc"

let s:cpo_save = &cpo
set cpo&vim

CompilerSet errorformat=
    \%-G%.%#:\ build,
    \%-G%.%#preprocessing\ library\ %.%#,
    \%-G[%.%#]%.%#,
    \%E%f:%l:%c:\ %m,
    \%-G--%.%#

if exists('g:compiler_ghc_ignore_unmatched_lines')
  CompilerSet errorformat+=%-G%.%#
endif

let &cpo = s:cpo_save
unlet s:cpo_save