See How (Not) To Ask A Question, but (completely off the wall guess here) perhaps you want to grep over the indexen rather than the array itself? 

my @array = qw( foo bar baz quux );
my @idx_of_eles_with_an_a = grep $array[ $_ ] =~ /a/, 0..$#array;

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The cake is a lie.
The cake is a lie.
The cake is a lie.

In reply to Re: Grep reutrn the occurance of a pattern by Fletch
in thread Grep reutrn the occurance of a pattern by Anonymous Monk

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