I have a function:
template<std::same_as<int&> T> void f(T value) {} Compiler gives me an error that I don't have a function with these arguments f(int) if I call it like this:
void g() { int a; int& b = a; f(b); } Why does the compiler assume that I use a regular type and not a reference and is there something I can do about it?
Unless you have a forwarding reference, the template type is never deduced as a reference type. Instead, it gets the type the reference refers to. In this case that means T is deduced as an int and that does not match int&. Instead you can use
template<std::same_as<int> T> void f(T& value) {} Which forces T to be an int, and then T& makes value a reference to the object passed to the function.
