So I'll take a stab at this, and maybe I'm missing what you're asking.

If you bless in a regular expression, it becomes a SCALAR, and as far as I can tell, there's no way to come up with the direct reference of it again, without putting it into regular expression context, like you have (but the only way I can see to do that is to actually use it). Then perl's internal magic kicks in, and blammo, it works.

However, this code below, works to determine whether a blessed thingy is a regexp:

#!/usr/bin/perl -w

use strict;
use warnings;
use Data::Dumper;

my $rex     = qr/[A-Z]o[A-Z]/;
my $bar = \$rex;
#my $blessed = bless qr/[A-Z]o[A-Z]/,'foo';
my $blessed = bless $bar, 'foo';

$\="\n";
$,=":\t";
print "Rex  ",ref $rex;
print "Bless",ref $blessed;

print "Rex  ",$rex,"WoW"=~$rex ? "WoW" : "---";
print "Bless",$blessed,"WoW"=~$$blessed ? "WoW" : "---";
print "Rex  ",$rex,"wow"=~$rex ? "!WoW" : "---";
print "Bless",$blessed,"wow"=~$$blessed ? "!WoW" : "---";
print "Rex  ",Dumper($rex);
print "Bless",Dumper($blessed);

print "Blessed bar", ref $$blessed;
[download]

lends me back:

Rex  :  Regexp
Bless:  foo
Rex  :  (?-xism:[A-Z]o[A-Z]):   WoW
Bless:  foo=SCALAR(0x80fd428):  WoW
Rex  :  (?-xism:[A-Z]o[A-Z]):   ---
Bless:  foo=SCALAR(0x80fd428):  ---
Rex  :  $VAR1 = qr/(?-xism:[A-Z]o[A-Z])/;

Bless:  $VAR1 = bless( do{\(my $o = qr/(?-xism:[A-Z]o[A-Z])/)}, 'foo' 
+);

Blessed bar:    Regexp
[download]

So you can work around it, by blessing references to references in, thus making the internal reference type of 'ref' and then maybe you don't have that layer of blessed magic-ness to work around. Is it because there is no way to put a scalar in regexp context without actually running it?

    --jb