Scala specification says: If there are several eligible arguments which match the implicit parameter’s type, a most specific one will be chosen using the rules of static overloading resolution. https://www.scala-lang.org/files/archive/spec/2.13/07-implicits.html#implicit-parameters The relative weight of an alternative A over an alternative B is a number from 0 to 2, defined as the sum of 1 if … Read more
Looks like your situation is like this: struct A { void f(); }; struct B { void f(int); }; struct C : A, B { }; int main() { C c; c.B::f(1); // not ambiguous c.f(1); // ambiguous } The second call to f is ambiguous, because in looking up the name, it finds functions … Read more
5.5 is a double, but none of your functions take a double argument. So, the compiler gets confused on whether to call the function with the int parameter, or the function with the float parameter. So, you get a an error saying it is ambiguous. That is why when you changed the function to have … Read more