Re: How = delete would work ?
On 9 Feb., 19:52, gute...@gmail.com wrote:
Would I be able to pass a class declared like this:
struct X {
X(X&) = delete;
template<class Y>
X(Y const&) {}
};
by value, like in function as this one:
void f(X x);
How does the function call look like? Overload resolution prefers non-
templates over templates. This is why in case of non-const lvalues the
deleted copy constructor is selected which would result in a
compilation error. For const arguments and/or rvalue arguments the
template-constructor is selected (I think) because these arguments are
not allowed to bind to X&.
X& source_x_lvalue();
X&& source_x_rvalue();
int main() {
f(source_x_lvalue()); // error, picks deleted X(X&)
f(source_x_rvalue()); // ok, picks template X(Y const&) with Y=X
f(42); // ok, picks template X(int const&) with Y=int
}
@terminator: "=delete" and "&&" are C++0x extensions.
Cheers!
SG
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