You have two capturing parens in the pattern, so the match operator returns two captures when the match operator is successful. Always.

Here's a couple of other solutions: 

my @hits = grep defined, m/(?:c(a)|k(t))/g;

[download]
my @hits;
while ( m/(?:c(a)|k(t))/g ) {
   push @hits, defined $1 ? $1 : $2;
}

[download]

The last one is extensible too: 

my @hits;
while ( m/(?:c(a)|k(t)|k(k))/g ) {
   push @hits, defined $1 ? $1
             : defined $2 ? $2
             : $3
}

[download]

In reply to Re: empty hits with regex by ikegami
in thread empty hits with regex by Anonymous Monk

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