显示空白字符

whitespace-mode

将制表符替换为空格

.emacs: (setq-default indent-tabs-mode nil)

remove tabs in an existing file: C-x h M-x untabify

does the opposite: M-x tabify

相关连接

EmacsWiki/Tabs Are Evil

参考文献

EmacsWiki/Show White Space
EmcasWiki/No Tabs