[arnehormann]

Because of the implicit thing! The api designer doesn't have to write the interface, you can do it yourself. As long as naming conventions are kept to and the signature matches, you can apply this anywhere.

Imagine a close() interface in Java. There isn't one - but having a try {...} finally { x.close(); } can be very useful sometimes. But having interface graphs made of granular interfaces makes everything slow and causes a lot of complexity when you try to think about your type hierarchy. That's why interfaces always just grow and you can't use them any longer because other classes only implement part of the api. Something usable for all of awt, swing, file handling, random foreign libraries? Unthinkable. Also, adding something in a later release (like CharSequence in 1.4) can have a wide ranging impact and requires you to change a lot of code.

In Go, you just add an interface from the union set of multiple structs api - and you can use it. No matter who wrote those structs. The value is enormous. Think of it as something like dependency injection at compile time.

[mschulze]

>Imagine a close() interface in Java. There isn't one

https://docs.oracle.com/javase/7/docs/api/java/lang/AutoClos...

You can even leave out the finally when you use an autocloseable resource.

    //r will be closed no matter what
    try(Resource r = getResource()) {

    } catch(SomeException e) {

    }

[arnehormann]

My Java is getting rusty... I read about this sometime somewhere but forgot it, thanks! I should have picked something like "String getText()", then.

[pjmlp]

> Because of the implicit thing!

Known as structural typing and available in most modern languages.

[icebraining]

available in most modern languages

Well, "modern" is an ill-defined concept. As far as I'm aware, structural typing is not really that common, is it? Besides OCaml and Scala, is there any relevant (used outside of academia) language that supports it?

[raverbashing]

Like duck typing?

[LBarret]

I suspect this is like duck typing with some verification before compilation : the compiler checks that the object sent as parameter implements the correct interface.