Not sure, but what about a combination of join and index? I understand that both these functions are quite fast... Something like:
sub s_in_a {
    my $s = shift;
    my $joined = '#' . join('#', @_) . '#';
    if (index($joined, "#$s#") >= 0) {
        return 1;
    }
    else {
        return 0;
    }
}

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In reply to Re: boolean IN(); function in perl like by mlh2003
in thread boolean IN(); function in perl like by Frank John

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