vimの読み込みオーダー
c. Five places are searched for initializations. The first that exists is used, the others are ignored. The $MYVIMRC environment variable is set to the file that was first found, unless $MYVIMRC was already set and when using VIMINIT. I The environment variable VIMINIT (see also compatible-default) (*) The value of $VIMINIT is used as an Ex command line. II The user vimrc file(s): "$HOME/.vimrc" (for Unix) (*) "$HOME/.vim/vimrc" (for Unix) (*) "s:.vimrc" (for Amiga) (*) "home:.vimrc" (for Amiga) (*) "home:vimfiles:vimrc" (for Amiga) (*) "$VIM/.vimrc" (for Amiga) (*) "$HOME/_vimrc" (for Win32) (*) "$HOME/vimfiles/vimrc" (for Win32) (*) "$VIM/_vimrc" (for Win32) (*) "$HOME/config/settings/vim/vimrc" (for Haiku) (*) Note: For Unix and Amiga, when ".vimrc" does not exist, "_vimrc" is also tried, in case an MS-DOS compatible file system is used. For MS-Windows ".vimrc" is checked after "_vimrc", in case long file names are used. Note: For Win32, "$HOME" is checked first. If no "_vimrc" or ".vimrc" is found there, "$VIM" is tried. See $VIM for when $VIM is not set. III The environment variable EXINIT. The value of $EXINIT is used as an Ex command line. IV The user exrc file(s). Same as for the user vimrc file, but with "vimrc" replaced by "exrc". But only one of ".exrc" and "_exrc" is used, depending on the system. And without the (*)! V The default vimrc file, $VIMRUNTIME/defaults.vim. This sets up options values and has "syntax on" and "filetype on" commands, which is what most new users will want. See defaults.vim.
以下の5か所を検索し、最初に引っかかったものが適用される。