dimes has asked for the wisdom of the Perl Monks concerning the following question:

I am in the midst<sp?> of reading apocalypse5 and have run across a listing if expresions based on "?". Some are obvious, some not so much. Could one or more of the local Monks possibly take a moment to do a rundown of what exactly they all mean...and maybe in what situations you might use them? Thanks, John

Below are the expressions: 

    (??{...})
    (?{...})
    (?#...)
    (?:...)
    (?i:...)
    (?=...)
    (?!...)
    (?<=...)
    (?<!...)
    (?>...)
    (?(...)...|...)

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Re: ? expresions from Apocalypse5
by Juerd (Abbot) on Jun 05, 2002 at 14:32 UTC

    They are discussed in perlre, part of the standard documentation that comes with perl. You will probably have it installed on your system. It can also be found at http://perldoc.com, and at this monastery (but hopefully not for long). 

    - Yes, I reinvent wheels.
- Spam: Visit eurotraQ.

[reply]
      (Juerd is, of course, referring to the fact that the copy on PerlMonks is outdated.)

      Makeshifts last the longest.

[reply]

        (Juerd is, of course, referring to the fact that the copy on PerlMonks is outdated.)

        No, not really. perlre is one of the documents that is useful even if it isn't the most recent version.

        Some things have been corrected, \x, unicode features, posix character classes, \z have been added. It is true that the (?...) stuff is a lot better in newer versions, though.

        I was more refering to the "friendly" manual than to the fact you mention . I expect the PerlMonks documentation problem to be resolved soon... 

        - Yes, I reinvent wheels.
- Spam: Visit eurotraQ.

[reply]
Re: ? expresions from Apocalypse5
by jryan (Vicar) on Jun 05, 2002 at 20:49 UTC
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