No Matching function call to templated function with const parameters

Question

I have a function that is defined as follows:

template < class T> T doSomething(const T value, const T value2, const T value3)
{
   T temp = value;
       //Do stuff
   return temp ;
}

in my main, I go to call it as follows:

doSomething(12.0, 23.0f, 2.0f);

I get an error saying no matching function for call doSomething(double, float, float).

I tried to used const_cast but it didn't seem to fix the issue. Any help would be appreciated.

Answer 1

It's not about the const, but about that T cannot be both double and float at the same time.

If you have a non-template function, one or more parameter can be promoted (or converted) to the parameter type. With a template function, the compiler will have to start by determining what the template type is supposed to be. Here it cannot decide.