What follows is a module I wrote quite some time ago (as a proof of concept) that "fixes" index in a different way. It returns undef if there is no match, and the position of the match otherwise - however, if it matches at the beginning of the string, "0 but true" is returned.

package Perl;

use Exporter;

use vars qw /@ISA @EXPORT @EXPORT_OK %EXPORT_TAGS/;

@ISA         = qw /Exporter/;
@EXPORT      = qw /index/;
@EXPORT_OK   = qw //;
%EXPORT_TAGS = ();


sub index {
    my $result;
    $result = 2 == @_ ? CORE::index ($_ [0], $_ [1])
                      : CORE::index ($_ [0], $_ [1], $_ [2]);
    $result < 0 ? undef : $result || "00";
}


1;

__END__
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-- Abigail