I'm not entirely sure I understand what you're trying to achieve, but dereffing and stringifying a qr// ref gives you a usable pattern string. For example: 
my $re1 = qr{([0-4])};
my $re2 = qr{([5-9])};

my %hash = ("$$re1" => "foo", "$$re2" => "bar");

$_ = "-5-";
for my $re (keys %hash) {
    print "match: ($1) $hash{$re}\n" if /$re/;
}

# outputs:
# match: (5) bar

[download]
Of course in the above it's now re-compiling the regex when executing it.

Dave.

In reply to Re: how to use string RE (against $_ and capture) by dave_the_m
in thread how to use string RE (against $_ and capture) by perl-diddler

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