Re: Pointer to virtual method in child class as template parameter
change B to the following, then the code works on ICC 9.1 and MSVC 8.0
class B : public A {
public:
virtual void doSomething() = 0;
}; // extended interface
That's what I'm using as a workaround too. For large interfaces that
obviously gets quite ugly.
My humble explanation is that non-type template parameter does not
allow implicit type conversion
Indeed, thanks for the hint. Section 14.3.2.5 of the standard states
"For a non-type template-parameter of type pointer to member function,
no conversions apply"
and Section 5.3.2.1 gives an example which implies that &B::doSomething
should have type void (A::* )().
The combination of these rules seems to cause quite an arbitrary
restriction of template parameters.
I'm also wondering why &B::doSomething has type void (A::* )(). If I had
wanted an A member function pointer I would have taken &A::doSomething
in the first place.
Stephan
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