Re: inhibit compiler warning C4624 for a class hierarchy

From:

"Tom Widmer [VC++ MVP]" <tom_usenet@hotmail.com>

Newsgroups:

microsoft.public.vc.language

Date:

Wed, 17 Jan 2007 15:15:50 +0000

Message-ID:

<eRGdhpkOHHA.4604@TK2MSFTNGP06.phx.gbl>

Ben Voigt wrote:

"Igor Tandetnik" <itandetnik@mvps.org> wrote in message
news:OxDS7RkOHHA.4172@TK2MSFTNGP04.phx.gbl...

"Ben Voigt" <rbv@nospam.nospam> wrote in message
news:eSHsMAkOHHA.3872@TK2MSFTNGP06.phx.gbl

f(1); // calls Y::f(double)

So it does now, without any new keyword.

I rather thought that Y::f(double) declared an overload of X::f(int)
and X::f(int) was a closer match for this call site...

Y::f(double) doesn't overload X::f(int) - it hides it. Name lookup stops
at the nearest enclosing scope where the name is found. If there are
several functions with this name _in that scope_, then overload resolution
kicks in. The net result is that a method in a derived class hides all the
methods with the same name in the base class, whether having the same or
different signature.

Thanks, I did not know that.

Is that also true when the derived class contains an override of a virtual
function defined in the base... that is, does overriding one overload hide
all others?

Yes. Virtual functions do not affect name lookup - polymorphism and name
lookup are orthogonal.

Tom