Difference between generic argument constrained to an interface and just using the interface

Question

What is the difference between this:

void MyMethod(IMyInterface value)
{
    //...
}

and this:

void MyMethod(T val         


        

Answer 1

Another subtle difference is that you can't overload a method only on constraints (constraints aren't part of the signature of the method):

This is illegal:

void MyMethod(T value) where T : IMyInterface
{
    //...
}

void MyMethod(T value) where T : IMyInterface2
{
    //...
}

while this is legal:

void MyMethod(IMyInterface value)
{
    //...
}

void MyMethod(IMyInterface2 value)
{
    //...
}