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This is an excerpt from the latest version perlfaq6.pod, which
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6.13: 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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