I can offer you some simplification.

First, the regex2 sub doesn't have to use eval, as the normal closure mechanism combined with //o should give you the semantics you have now. Also, you're going to the trouble of initializing your returned count to zero, then if it stays zero, you're returning undef. Better just to leave it uninitialized and use ++ on it; the results will be as you want. Thus: 

sub regex2 {
    my $pat = shift;
    sub { my $count; ++$count while /$pat/iogx; $count };
}

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    -- Chip Salzenberg, Free-Floating Agent of Chaos

In reply to Re: Implementing variable-width negative lookbehind assertions? by chip
in thread Implementing variable-width negative lookbehind assertions? by ToasterLeavings

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