untested. idea was to extend functionality to as many words as passed, and get a return that was a bit more informative than just the number of shared characters. is the idea ok, code aside? 
$class = ‘[a-z]’;
@commonChars = compareChars( $class );

sub compareChars {
    $regex = shift;
    $requiredCount = @ARGV;
    for ( $i=0; $i<=$#ARGV; $i++ ) {
        while ( $ARGV[$i] =~ m/($regex)/gi ) {
            $found{$1} = $i + 1;
        }
    }
    while ( ( $key, $value ) = each %found ) {
        push @answer, $key if $value == $requiredCount;
    }
    return @answer;
}

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In reply to Re: Optimizing a string processing sub by clairudjinn
in thread Optimizing a string processing sub by spurperl

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