Operands and return types of the operator are fixed

The operator is truly polymorphic: it's the same runtime function that may work on multiple types. We require that resolving the argument types from right to left trivially resolves all type variables declared in the operator type.

The operator is ambiguous and requires the types of its arguments to be known before it can be typed, using a pre-defined table

Explicit monomorphic versions of the overloaded operators