How to use regular expressions in perl language
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A regular expression describes a pattern of string matching, which can be used to check whether a string contains a certain substring, replace a matching substring, or extract a substring from a string that meets a certain condition. Perl language regular expression function is not...
A regular expression describes a pattern of string matching, which can be used to check whether a string contains a certain substring, replace a matching substring, or extract a substring from a string that meets a certain condition.
Perl language regular expressions are very powerful, basically the most powerful in common languages, and many languages refer to Perl regular expressions when designing regular expression support.
Perl has three forms of regular expressions: matching, substitution, and transformation:
Match: m//(also abbreviated as//, omitting m)
Replace: s///
Conversion: tr///
These three forms are generally and =~ or!~ Use together,=~ means match,!~ indicates a mismatch.
Pattern matching has some common modifiers:
i Ignore case in mode
g Global match
Regular expression rules. Matches all characters except newline * Matches the x string zero or more times, but matches the fewest possible times? Matches 0 or 1 x string.* Match any character 0 or more times [] Matches characters [^] within [] Match does not match characters in []^ Matches the character at the beginning of the character $ Matches characters at the end of characters\d Matches a numeric character, same syntax as [0-9]\D Matches a non-numeric character\w Match letters or numbers\W Match non-English letters or numbers\s Spaces, same syntax as [\n\t\r\f]\S Non-blank thanks for reading! About "how to use regular expressions in perl language" this article is shared here, I hope the above content can be of some help to everyone, so that everyone can learn more knowledge, if you think the article is good, you can share it to let more people see it!
