in reply to Undefined regexp objects?

qr// doesn't return a reference. Try: 
use strict;
use warnings;

my $r = qr/Delectable/;
print $r;

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Update: ihb is quite right. I should have qualified that as scalar reference.

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Re: Re: Undefined regexp objects?
by ihb (Deacon) on Jan 15, 2003 at 23:53 UTC
    qr// does indeed return a reference, try 
      print ref(qr//)

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    This object stringifies through, so you can interpolate it into other patterns.

    ihb
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[d/l]
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      In fact... you can also call methods off of it and rebless the object into a different package and it keeps it's Regexp nature.

      use strict;
use warnings;

my $r = qr/test/;
print $r -> match( 'test' ) ? "Match\n" : "No match\n";
bless $r, 'beans';
print $r -> match( 'test' ) ? "Match\n" : "No match\n";

package beans;
sub match { $_[1] =~ $_[0] }

package Regexp;
sub match { $_[1] =~ $_[0] }

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        ... rebless the object into a different package and it keeps it's Regexp nature

        Not really. The Regexp nature will disappear, you bless away that. What won't disappear is the fact that the blessed thingy is a MG, i.e. magical. But the Regexp nature will disappear. For instance, you can no longer interpolate the pattern since the string overloading was done by Regexp. So /$re /x won't work the intended way. Note that for /$re/ no interpolation is done, so that still works as expected.

        ihb
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        FYI, Damian Conway has a section on blessing regular expression references in his Object Oriented Perl book.

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