从perl的角度来看vim regexp：用反斜杠转义的特殊字符

Question

Imagine, we have to construct a regexp in vi/vim. Which special characters we have to escape with backslash?

By special characters I mean the following chars: {}|()-[]+*.^$?

Seems like we have to escape: {|()+?

And leave as is: }^$*.[]-

Thanks.

ps AFAIK, we have no '?' character in vi/vim but '=' instead which should be also escaped by backslash.

Answer 1

我认为Vim上有关魔术角色的文档将为您提供明确的清单。

Answer 2

In vim:

:help magic

Answer 3

I think the simplest way, that will work regardless of vim's magic setting, is

let re = '\V' . escape(fixed_string, '\')

\\V disables magic entirely from that point onward in the RE. This means that anything not preceded by a single backslash (well, technically by an odd number of backslashes) is a normal character. Since we escape any backslashes in the fixed string, there can be no magic characters contained in it.

Remember that with \\V in effect, you have to backslash-prefix any RE meta-characters. So if you're looking for a line that entirely consists of the fixed string, you would

let full_line_re = '\V\^' . escape(fixed_string, '\') . '\$'

Also keep in mind that vim's ignorecase and smartcase settings will affect RE behaviour. The \\C (case-sensitive) and \\c (case-insensitive) switches work the same way as \\V : they will override those settings for the part of any regexp which follows them.