Earlier quoted context omitted.
> Which means you can declare an interface that foreign packages already conform to, and then freely use them. But you cannot do the reverse: you cannot make a type from a foreign package conform to your interface by adding new methods to it. This is because, with structural typing, it's not safe to add methods to types in other packages, since if packages B and C both were to add a conflicting method Foo to a type f…
> But you cannot do the reverse: you cannot make a type from a foreign package conform to your interface by adding new methods to it. I thought you could. You don't add the methods directly to it, but you can easily embed the foreign type into a new type that confirms to the interface you want. type FooWrapper struct { Foo } func (fw FooWrapper) SomeFunc() { ... }
Re: Go 1.6 is Released
#151That's making a new type, which causes a lot of friction. For example, a []Foo array is not castable to a []FooWrapper array without recreating the entire thing.