$str = 'aaaaa';
$str =~ s/a+/b/;

[download]

Since '+' is greedy, you end up with 'b' in $str.
If '+' wasn't greedy, you'd end up with 'baaaa' in $str.

You can make '+' non-greedy by following it with a '?':

$str1 = $str2 = '111b222c333c444';
$str1 =~ s/b.+c//;
# $str1 contains '111444'.
$str2 =~ s/b.+?c//;
# $str2 contains ''111333c444'.

[download]

'*' and '?' can similarly be modified with a '?'.

Both greedy and non-greedy are useful. Use whichever one you need in a particular situation.

In reply to Re: greedy search by ikegami
in thread greedy search by palette

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