On Friday, 2 August 2013 at 20:34:04 UTC, SteveGuo wrote:
I'm not an expert on programming language, if I made a naive
issue, just forgive me:p
Yes, this would have been better asked in .learn, but no matter.
Can we declare a template function like this?
auto Add(a, b) // Note a, b do not have type, that means a and
b use template type
{
return a + b;
}
auto Sub(a, int b) // a uses template type, b is fixed to int
{
return a - b;
}
When we call the function,
Add(1, 2); // deduced to be Add(int, int);
Add(1.5, 2.3); // deduced to be Add(double, double);
Add(1.5, "Hello"); // compiler error!
Sub(1.5, 1); // deduced to be Add(double, int);
Sub(1, 1.1); // deduced to be Add(int, int); compiler error,
double can not converted to int automatically
Types can be deduced automatically, so you can simply write:
auto Add(A, B)(A a, B b);
The type is explicit in the *declaration*, but when you call
"add(1, 2)", the compiler will *deduce* A and B to be int.
Ditto for sub:
auto Sub(A a)(A a, int b);
