----- Original Message ----- From: "Peter Dimov" <[EMAIL PROTECTED]> Newsgroups: gmane.comp.lib.boost.devel Sent: Thursday, December 12, 2002 6:24 PM Subject: Re: Formal review: Optional library
> From: "Fernando Cacciola" <[EMAIL PROTECTED]> > > > optional<T> m(t); > > > > > > > foo(m, m); // comparison inside yields false > > where foo is > > void foo(optional<T> const &, optional<T> const &); > > > > > > > Nop... :-) > > > > it compares true because get_pointer(x)==get_poiner(x) is true for any x, > > whether initialized or not. > > True. Had foo been > > void foo(optional<T>, optional<T>); > > or had the call been > > foo(optional<T>(t), optional<T>(t)); // corresponds to foo(&t, &t) > > I would have been right. > Ouch! Nasty :-) OK, deep-copyness breaks pointer-semantic at some point no matter how much you try to fake it.... But then I have to go back to my original decision of disallowing relational operations directly, because they won't work as I wanted (with semantics invariant under type change). William? Fernando Cacciola _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost
