Wouldn't blessing a copy of the reference in order to extract the address work, and allow the blessed copy to be discarded leaving the original unmodified?

Nope. Blessedness is associated with the referent not the reference. For example:

use Test::More 'no_plan';

my $original = bless {}, 'Something';
isa_ok $original, 'Something';

my $copy = $original;
bless $copy, 'SomethingElse';

isa_ok $original, 'SomethingElse';

__END__

ok 1 - The object isa Something
ok 2 - The object isa SomethingElse
1..2

[download]

In reply to Re^5: A Scalar::Util::refaddr Oddity by adrianh
in thread A Scalar::Util::refaddr Oddity by Zaxo

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.