Voice your opinion! (overload resolution)
Reid M. Pinchback
reidmp@mit.edu
Thu Sep 3 05:16:00 GMT 1998
I'm trying to figure out if part of the overload resolution
behaviour of the 19980824 is or isn't a bug w.r.t. CD2,
but I'm still not sure. The relevant sections appear to be:
* all of 13 [over]/13-1
* 14.6.4.3 [temp.dep.conv]/14-26
* 14.8.3 [temp.over]/14-41
Here's the deal. Case 3 below results in the error:
no matching function for call to 'f (int, B)'
while the first two cases below yield a match. The same
behaviour is seen if a binary operator is used in place
of a function. Should case 3 fail, or the user-defiend
conversion in the templated class by used (presumably
by the implicit instantiation A<int>) ?
#define CASE4
#if defined(CASE1)
struct A {int x; A(int v):x(v){} };
struct B {int x; B(int v):x(v){} };
int f(A a, B b) { return a.x+b.x; }
#elif defined(CASE2)
template <class T> struct A {T x; A(T v):x(v){} };
struct B {int x; B(int v):x(v){} };
int f(A<int> a, B b) { return a.x+b.x; }
#elif defined(CASE3)
template <class T> struct A {T x; A(T v):x(v){} };
struct B{int x; B(int v):x(v){} };
template <class T> int f(A<T> a, B b) { return a.x+b.x; }
#endif
main (int argc, char*argv[]) {
int c=f(1,B(1));
}
====================================================
= Reid M. Pinchback =
= I/T Delivery, MIT =
= =
= Email: reidmp@mit.edu =
= URL: http://web.mit.edu/reidmp/www/home.html =
====================================================
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