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0 pointspeterwwillis12y ago0 comments

I'm probably heavily biased, but to me Perl is the best command-line regex tool. Perl was invented to gather data and report on it, and its regex engine is incredibly fast and powerful. As an added bonus it supports some Python and PCRE-specific extensions. But this Q app is useful for people who either don't know Perl or can get what they need done faster with SQL than with scripting.

In terms of 'verbosity' you can embed comments inside a regular expression, or build a regular expression over multiple lines, or make a set of regex objects and interpolate them into larger regex's. Perl has copious amounts of documentation to help you understand the many ways to use regexs in Perl.

http://perldoc.perl.org/perlrequick.html http://perldoc.perl.org/perlretut.html http://perldoc.perl.org/perlfaq6.html#How-can-I-hope-to-use-...

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theOnliest12y ago

> As an added bonus it supports some Python and PCRE-specific extensions.

This is a bit of a strange thing to say, since nearly all of the advanced regex features showed up in Perl first. PCRE stands for "Perl-compliant regular expressions," so there's certainly no extensions there that didn't originally come from Perl. I'm less sure about Python, but I get the sense that they borrow from Perl regular expressions as well.

peterwwillisOP12y ago

http://perldoc.perl.org/perlre.html#PCRE/Python-Support

  PCRE/Python Support
  
  As of Perl 5.10.0, Perl supports several Python/PCRE-specific extensions to the
  regex syntax. While Perl programmers are encouraged to use the Perl-specific
  syntax, the following are also accepted:
  
      (?P<NAME>pattern)
      Define a named capture group. Equivalent to (?<NAME>pattern).
  
      (?P=NAME)
      Backreference to a named capture group. Equivalent to \g{NAME} .
  
      (?P>NAME)
      Subroutine call to a named capture group. Equivalent to (?&NAME).

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