Because that idiom fails if $object overloads addition to do something else.

Doh! (Can you tell I don't mess with overloading much? Wasn't even on my radar screen.) OK, then, quick perusal of overload reveals the StrVal function, which can get us back to the original "grab the right substring and convert" approach without the reblessing. 

use strict;
use warnings;
use Scalar::Util qw( refaddr );

package Foo;
use overload
    '0+'    => sub { 0 },
    q{""}   => sub { "Some Object" },
    fallback => 1;

package main;
use overload;

sub refaddr_pp {
    return if not ref $_[0];
    overload::StrVal($_[0]) =~ /0x(\w+)/;
    return hex $1;
}

my $obj = bless {}, 'Foo';
my $ref = {};

print 'stringify  $obj: ', "$obj",           "\n";
print 'refaddr    $obj: ', refaddr($obj),    "\n";
print 'refaddr_pp $obj: ', refaddr_pp($obj), "\n\n";
print 'stringify  $ref: ', "$ref",           "\n";
print 'refaddr    $ref: ', refaddr($ref),    "\n";
print 'refaddr_pp $ref: ', refaddr_pp($ref),    "\n\n";

[download]

Prints

stringify  $obj: Some Object
refaddr    $obj: 155892768
refaddr_pp $obj: 155892768

stringify  $ref: HASH(0x94abd10)
refaddr    $ref: 155893008
refaddr_pp $ref: 155893008

[download]

-xdg

Code written by xdg and posted on PerlMonks is public domain. It is provided as is with no warranties, express or implied, of any kind. Posted code may not have been tested. Use of posted code is at your own risk.

In reply to Re^4: A Scalar::Util::refaddr Oddity by xdg
in thread A Scalar::Util::refaddr Oddity by Zaxo

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