I was hoping that this might be done using the "overload" module, but couldn't make it work. You can stringify a blessed reference into anything you like, but we know that "undef" is not a blessed reference so that doesn't help. Then I came up with this:

perl -e "BEGIN{use overload; overload::constant( integer => sub{ return 'forty two' }) } print 42"

And that's not what you wanted, but it's pretty cool, huh? The problem is that overload::constant only works with actual constants, not undef values.

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

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