Re: Does covariant return types hold for non-virtual?
On 11.05.2010 16:28, * DeMarcus:
Hi,
In ?10.3/5 they explain covariant return types. Do they hold also for
non-virtual functions? I.e. is this legal on all compilers according to
the standard?
As noted else-thread the issue of covariant return types is irrelevant to your question.
struct A_helper
{
A& fnc();
};
struct B_helper
{
B& fnc();
};
struct A : A_helper
{
};
struct B : A, B_helper
{
};
The inheritance structure would look like this.
A_helper
/
/
A
|
| B_helper
| /
| /
B
So B would have both following
A& fnc()
B& fnc()
That's OK. Until you try to /call/ fnc on a B object. At that point two declarations of fnc will be found in different base classes, and the compiler doesn't even consider the result types or anything (e.g. it doesn't check whether one of methods are const), it just has a clear ambiguity at hand.
Cheers & hth,
- Alf
--
blog at <url: http://alfps.wordpress.com>
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