I hope you won't take this the wrong way, but that code is very hard to read. It's cool to do things like this with eval, but not a good idea from a maintenance perspective most of the time. I would have arranged it something like this (untested): 
my @matches = get_matches($file);

sub get_matches {
    my $file = shift;
    return unless (-e $file && -r _);

    local *FH;
    sysopen FH, $file, O_RDONLY;
    flock FH, 8;
    map { chomp; qr/$_/ } <FH>;
}

[download]
I don't think the map is a big deal here, since you want the return value. I'm not sure it's worth messing around with sysopen though (I've never needed to use it, so I don't even know if it still works the way I rearranged it), and hard-coding the constant "8" is probably not a good idea either. I expect you know all this and were just posting to point out other things, but maybe someone else reading this didn't.

In reply to Re: Scope and Context by perrin
in thread Scope and Context by rob_au

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