Taking the example from the post I commented on, the code had split(/(?:"([^"]*)"|\s+)/. The outer (?:) is actually useless and can be removed. Applying it gives:
use Data::Dumper;
$Data::Dumper::Terse = 1;


print Dumper $_ for split /"([^"]*)"|\s+/, 'this "is" an "example"';
__END__
'this'
undef
''
'is'
''
undef
'an'
undef
''
'example'

[download]
Update: rewrote following paragraph for clarity.

The split splits the string 'this "is" an "example"' up everywhere there is a quoted string or repeated whitespace. This yields the substrings "this", "", "", "an", and "". Because there was one set of capturing parentheses in the split pattern, there will be one extra value returned for each split (this is a feature that allows you to split on several delimiters and see which delimiter was used). These extra values are undef, "is", undef, undef, and "example". Where the split was on whitespace, the value is undef because the capturing parentheses were not actually used in the match. Where the split was on a quoted string, the value is what was in the quotes.

In reply to Re: Re: Re: Re: Re: In need of a stupid regex trick by ysth
in thread In need of a stupid regex trick by 87C751

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.