vim tab和空格相互替换

.vimrc:
" add by school1024.com
set ts=4
set softtabstop=4
set shiftwidth=4
set expandtab
set autoindent

TAB替换为空格

:set ts=4
:set expandtab
:%retab!

空格替换为TAB

:set ts=4
:set noexpandtab
:%retab!

参考：https://cloud.tencent.com/developer/article/1722322