FAQ 6.12: What does it mean that regexes are greedy? How can I get around it?

From: PerlFAQ Server (comdog_at_panix.com)
Date: 12/28/04 

Date: Tue, 28 Dec 2004 17:03:00 +0000 (UTC)

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6.12: What does it mean that regexes are greedy? How can I get around it?

    Most people mean that greedy regexes match as much as they can.
    Technically speaking, it's actually the quantifiers ("?", "*", "+",
    "{}") that are greedy rather than the whole pattern; Perl prefers local
    greed and immediate gratification to overall greed. To get non-greedy
    versions of the same quantifiers, use ("??", "*?", "+?", "{}?").

    An example:

            $s1 = $s2 = "I am very very cold";
            $s1 =~ s/ve.*y //; # I am cold
            $s2 =~ s/ve.*?y //; # I am very cold

    Notice how the second substitution stopped matching as soon as it
    encountered "y ". The "*?" quantifier effectively tells the regular
    expression engine to find a match as quickly as possible and pass
    control on to whatever is next in line, like you would if you were
    playing hot potato.

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