I've been asked why I used a package variable instead of a lexical variable. It's because regexps close around the lexicals that exist when they are first run.

                                       # pass  1   2   3
                                       #      --- --- ---
sub test {
   my @matches;
   '' =~ /
      (?{ push @matches, 'a' })
      (?{ print(scalar(@matches), "\n") })   # 1   2   3
   /xg;  
   print(scalar(@matches), "\n");            # 1   0   0
}

test() for 1..3;
[download]

A variable called @matches is created everytime test is called. The regexp always uses the variable from the first call.

---

---

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! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, 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, 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:
	&		&
	<		&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.