🚀 go-pugleaf

>>>>> "RL" == Roman Lechtchinsky <wolfro@cs.tu-berlin.de> writes:
RL> David Vandevoorde wrote:
>> 
>> >>>>> "RL" == Roman Lechtchinsky <wolfro@cs.tu-berlin.de> writes:
>> [...]
RL> class Base
RL> {
RL> virtual void f(int);
RL> };
>> 
RL> class Derived : Base
RL> {
RL> template<class T> void f(T);
RL> };
>> 
RL> Is this legal? If so, will the template function f(int) override
RL> Base::f(int)? If so, when will it be instantiated? And, last but not
RL> least, which section of the DWP handles this case? Thanks in advance.
>> 
>> I believe this is legal and the instantiated member function is not
>> virtual (i.e., no overriding), but my reason extrapolates the WPs
>> somewhat. I base this on the fact that the `signature' of a template
>> function includes the actual template arguments ([temp.over.link]
>> 14.10.4/3 in the April CD), and that when [class.virtual] 10.3/2
>> requires `same name', `name' really means template-id and not just
>> template-name ([temp.names] 14.1).
>> 

RL> IMO, this means that f cannot be overridden in Derived:

RL> class Derived : Base
RL> {
RL>  template<class T> void f(T);
RL>  void f(int);
RL> };

RL> would be a specialization which means that f doesn't override as it is
               ^^^^^^^^^^^^^^
To me more precise: it would be a ``guiding member-function declaration'',
if such a beast is supposed to exist (i.e., it declares a specialization,
but only to guide overloading resolution --- the definition is still
generated from the template). However...

RL> still a template ( [temp.over.spec] 14.10.5 ). Is this interpretation
RL> correct?

Frankly, I don't know. I can see three reasonable possibilities:

1) your interpretation,
2) it is not a guiding declaration but an overriding function.
   A guiding declaration could instead perhaps be declared via:

	struct Derived: Base {
	    template<typename T>
	    void f(T);
	    void f<int>(int); // Guiding member function declaration
	    void f(int);      // Virtual function overriding Base::f(int);
	};

3) it is simply illegal C++ code.

I suspect 1) is true, but I'm really not sure at all...

	Daveed
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