Re: [boost] Proposal --- A type-safe union

From: Fernando Cacciola (fcacciola_at_[hidden])
Date: 2002-06-13 09:04:03

----- Original Message -----
From: "Douglas Gregor" <gregod_at_[hidden]>
To: <boost_at_[hidden]>
Sent: Thursday, June 13, 2002 1:02 AM
Subject: Re: [boost] Proposal --- A type-safe union

> On Wednesday 12 June 2002 04:28 pm, Fernando Cacciola wrote:
> > AFAIK, a using-declaration is useful only when resolving 'conflicting'
> > signatures.
> > Unless I'm too sleepy already, if 'check' is not a virtual function, its
> > complete signature (argument types including) is what matters here.
> > In this case, since it is assumed that all the types in the list are
> > different, each checker sub-class would have its own version of check()
> > with a different signature than any other check() on the hierarchy.
There
> > shouldn't be any name-hiding to resolve.
>
> Reread 10.2/2, especially this sentence:
>   "A member name f in one sub-object B hides a member name f in a
sub-object A
> if A is a base class sub-object of B."
>
OK. I was too sleepy already :-)
Now it is so clear! I'm sorry for being so insistent.

(maybe I just badly wanted it to work since BCB doesn't like the using
declaration).

> Go ahead and look at the output of Brad's sample code with and without the
> using directive. With the using directive on GCC 3.1, one gets:
>
Yeah... I should have done this!

Sorry.

Fernando Cacciola
Sierra s.r.l.
fcacciola_at_[hidden]
www.gosierra.com