my ($match) = grep defined, $string =~ /<(ab)>|(ab)/;

[download]
or use (?(condition)...), taken almost literally from perlre: 
my ($quoted,$match) = $string =~ /(<)?(ab)(?(1)>)/x;
# or:
my $match = ($string =~ /(<)?(ab)(?(1)>)/)[1];

[download]

In reply to Re: Help with Regular Expression matching by ysth
in thread Help with Regular Expression matching by Anonymous Monk

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