SO上有很多关于 正则表达式否定的问题。
我不确定我是否理解为什么人们觉得需要否定正则表达式。
为什么不使用类似的东西grep -v
只显示与正则表达式不匹配的结果?
$ ls
april august december february january july june march may november october september
$ ls | grep ber
december
november
october
september
$ ls | grep -v ber
april
august
february
january
july
june
march
may