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Postings from February 2002
Dan Sugalski <dan@sidhe.org> wrote: > At 3:53 PM +0000 2/14/02, Dave Mitchell wrote: > >My outstanding niggle is when a typed variable is undef. I guess we > >need a generic Perl_Undef_But_Typed vtable type, which behaves mostly > >like the PerlUndef type, but saves a pointer to its 'real' vtable in > >self->data or whatever. When it's assigned to, it upgrades itself to > >its real type, then passes control to it's real type's assign method. > > That's a good point. I'll have to think about that a little bit. We > could either have an undef flag or something and take definedness > entirely out of the hands of the vtables, which would involve a conditional branch for every access of every PMC :-( > or use the "X or child of > X" mechnanism to allow for undefs as well. Have you any feel for what this child of X mechanism is?Thread Previous | Thread Next