Since the undef SV is shared between all undefined values, one could modify undef using a feature in Perl 5.8. (I only thought of this because of the solution to #13 of How's your Perl? (II)).

At the beginning of your program (possibly in a BEGIN block) (completely untested):

&Internals::SvREADONLY(\undef, 0);
undef = Object::EveryMethod->new;
&Internals::SvREADONLY(\undef, 1);

[download]

And override Object::EveryMethod for string/num/bool to behave like undef normally does.

"There is no shame in being self-taught, only in not trying to learn in the first place." -- Atrus, Myst: The Book of D'ni.

In reply to Re: The Null Mull (or, when OO needs more O) by hardburn
in thread The Null Mull (or, when OO needs more O) by brian_d_foy

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