http://www.perlmonks.org?node_id=961008

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

Hello,

Is anyone able to explain what this perl regex matches?

"999[89]\$"

Many thanks

Replies are listed 'Best First'.
Re: A regular expression
by dorko (Prior) on Mar 22, 2012 at 13:38 UTC
    I use YAPE::Regex::Explain to explain Regular Expressions: 
    use YAPE::Regex::Explain;
print YAPE::Regex::Explain->new(qr/999[89]\$/)->explain();

__END__

The regular expression:

(?-imsx:999[89]\$)

matches as follows:
  
NODE                     EXPLANATION
----------------------------------------------------------------------
(?-imsx:                 group, but do not capture (case-sensitive)
                         (with ^ and $ matching normally) (with . not
                         matching \n) (matching whitespace and #
                         normally):
----------------------------------------------------------------------
  999                      '999'
----------------------------------------------------------------------
  [89]                     any character of: '8', '9'
----------------------------------------------------------------------
  \$                       '$'
----------------------------------------------------------------------
)                        end of grouping
----------------------------------------------------------------------

    [download]

    Cheers,

    Brent

    -- Yeah, I'm a Delt.
[reply]
[d/l]
      that's a handy tool, thanks!
[reply]
Re: A regular expression
by JavaFan (Canon) on Mar 22, 2012 at 13:27 UTC
    Any string that contains either 9998$ or 9999$.
[reply]
[d/l]
[select]
      great, thanks very much!
[reply]
Re: A regular expression
by GrandFather (Saint) on Mar 22, 2012 at 20:15 UTC

    You should take a good look at least at perlretut, and probably at some of the other Perl regular expression documentation.

    True laziness is hard work
[reply]
Re: A regular expression
by planetscape (Chancellor) on Mar 24, 2012 at 22:54 UTC
[reply]

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