哪些字符可以用作正则表达式分隔符? [英] Which characters can be used as regular expression delimiters?

问题描述

哪些字符可以用作 Perl 正则表达式的分隔符?m/re/、m(re) 和 måreå 似乎都有效，但我想知道所有的可能性.

Which characters can be used as delimiters for a Perl regular expression? m/re/, m(re) and måreå all seem to work, but I'd like to know all possibilities.

推荐答案

来自 perlop:

通过 m，您可以使用任何一对非空白字符作为分隔符.

With the m you can use any pair of non-whitespace characters as delimiters.

所以什么都行，除了空格.完整的段落是:

So anything goes, except whitespace. The full paragraph for this is:

如果/"是分隔符，则初始 m 是可选的.使用 m 您可以使用任何一对非空白字符作为分隔符.这对于匹配包含/"的路径名特别有用，以避免 LTS(倾斜牙签综合症).如果 "?"是定界符，然后是?PATTERN 的仅匹配一次规则?适用.如果'"是分隔符，则不会对 PATTERN 执行插值.在标识符中使用有效字符时，m 后需要空格.

If "/" is the delimiter then the initial m is optional. With the m you can use any pair of non-whitespace characters as delimiters. This is particularly useful for matching path names that contain "/", to avoid LTS (leaning toothpick syndrome). If "?" is the delimiter, then the match-only-once rule of ?PATTERN? applies. If "'" is the delimiter, no interpolation is performed on the PATTERN. When using a character valid in an identifier, whitespace is required after the m.

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