Re: How to assign a non-const object to const reference

From:

"Igor Tandetnik" <itandetnik@mvps.org>

Newsgroups:

microsoft.public.vc.language

Date:

Wed, 3 May 2006 11:38:48 -0400

Message-ID:

<#86w4esbGHA.5116@TK2MSFTNGP02.phx.gbl>

Alamelu <Alamelu@discussions.microsoft.com> wrote:

Thank u so much Igor.
Was very much useful and informative.

When i followed the approach mentioned below, i didnt run into any
error const AClass& DerivedClass::Get()
{
return m_ObjA;
}

const AClass objA;
objA = derived.Get(); // Didnt get any error at this line.

Why is that so? Compiles, builds and works fine.

Are you sure you did this, and not

const AClass objA = derived.Get();

? These are again different - the former is assignment, the latter is
initialization. Basically, constness is suspended while the constructor
(copy constructor in this case) is running, otherwise you would never be
able to initialize member variables of any const object.
--
With best wishes,
Igor Tandetnik

With sufficient thrust, pigs fly just fine. However, this is not
necessarily a good idea. It is hard to be sure where they are going to
land, and it could be dangerous sitting under them as they fly
overhead. -- RFC 1925