This is an even more obvious:
$_='abcdefgh';
/^(a|abcdefg)(h|bc)/;
print "[$1] [$2]\n";

[download]
It prints [a] [bc]. The regexp engine clearly doesn't run through all possible combinations within (..|..|..) patterns.

In reply to Re^2: Greedy regexp matching: differences between man page and implementation? by perldeveloper
in thread Greedy regexp matching: differences between man page and implementation? by stijnvs

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