vim tab = 4 space

let _curfile = expand("%:t")
if _curfile =~ "Makefile" || _curfile =~ "makefile" || _curfile =~ ".*\.mk"
"Edit Makefile disable expandtab-function
set tabstop=4
set shiftwidth=4
set autoindent
set number
set noexpandtab
else
"Add below 3 line, set tab = 4 space
set tabstop=4
set shiftwidth=4
set expandtab
set autoindent
set number
endif