by arnaud.porterie:

It seems that the following code is not fully specified:

  type MyType int
  [...]
  var m MyType
  m += 0

I understand that 0 being an untype constant, it can be used in a binary operation with
a `MyType` operand. However, I cannot find what specifies that binary operations can be
used on operands of type `MyType` ("Arithmetic operators" paragraph isn't
really clear on that).