This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 115f. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.
2024-12-06
Is the comma expression in the following dependent?
template <class T> static void f(T) { } template <class T> void g(T) { f((T::x, 0)); } struct A { static int x; }; void h() { g(A()); }
According to the standard, it is, because 13.8.3.3 [temp.dep.expr] says that an expression is dependent if any of its sub-expressions is dependent, but there is a question about whether the language should say something different. The type and value of the expression are not really dependent, and similar cases (like casting T::x to int) are not dependent.
Mark Mitchell: If the first operand is dependent, how do we know it does not have an overloaded comma operator?
Rationale (October, 2004):
CWG agreed that such comma expressions are and ought to be dependent, for the reason expressed in Mark Mitchell's comment.