To answer your question, no, but it's not really the key issue. The problem is storage; I can't store a value of 1.5 in my original Vector2D, so I had to reimplement it.
If that sounds silly (why not just change the original Vector2D to floats?) imagine you're implementing a game, for example, and you want to store game objects in sets. You can't just write one type-safe Set structure – you have to implement Monster1Set, Monster2Set, PlayerSet, Coin1Set...
Basically, any time you want to go outside of Go's built-in array and dictionary types, you run into problems.
If that sounds silly (why not just change the original Vector2D to floats?) imagine you're implementing a game, for example, and you want to store game objects in sets. You can't just write one type-safe Set structure – you have to implement Monster1Set, Monster2Set, PlayerSet, Coin1Set...
Basically, any time you want to go outside of Go's built-in array and dictionary types, you run into problems.