You could play tricks with tie -- I'm not advocating it, but it is a possibility depending upon your purpose.

{ 
    package Undef; 
    sub TIESCALAR{ bless \pop, 'Undef';} 
    sub STORE{ $$_[0] = $_[1]; } 
    sub FETCH{ defined $$_[0] ? $$_[0] : 0 } 
};

tie $x, 'Undef';

$x = 0; print "'$x'";
'0'

$x = ''; print "'$x'";
''

$x = undef; print "'$x'";
'0'

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Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"Think for yourself!" - Abigail

In reply to Re: Stringifying undefs by BrowserUk
in thread Stringifying undefs by BUU

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