Although I suspect you know, for anybody else reading this a slight clarification:

is that matches are greedy (unless you tell them not to be) and will get the largest match they can

This is not strictly true with perls NFA based regex engine. They will match the leftmost longest match that they can. This doesnt mean the longest possible match as a DFA based regex engine (egrep) would provide. Thus 

"AAABBBBBBBBAAAAAAAAAAAA"=~m/A+|A+B+A+/;

[download]
Will match "AAA" and not the entire string. But a DFA based regex engine would match the entire string.

OTOH reversing the option 

"AAABBBBBBBBAAAAAAAAAAAA"=~m/A+B+A+|A+/;

[download]
Would match the entire string using either engine.

Yves / DeMerphq
---
Writing a good benchmark isn't as easy it might look.

In reply to Re: Re: regex capturing problem by demerphq
in thread regex capturing problem by pike

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.