Why do Ruby people say they don't need interfa

Question

Does ruby have something different to other OOP languages (eg: PHP) that makes interfaces useless? Does it have some kind of replacement for this?

Edit:

Some clarifications:

• In other languages (eg: PHP), you don't "need" interfaces (they are not mandatory at code level). You use them to make a contract, to improve the architecture of the software. Therefore, the affirmation 'in ruby you don't need interfaces / in other languages you need interfaces because XXX' is false.

• No, mixins are not interfaces, they are a complete different thing (PHP 5.4 implements mixins). Have you even used interfaces?

• Yes, PHP is OOP. Languages evolve, welcome to the present.

Answer 1

Depends what you mean by interface.

If by interface you mean a concrete object that exists in your language that you inherit from or implement then no you don't use interfaces in a language like ruby.

If you mean interface as in objects have some well documented interface then yes of course, objects still have a well documented interfaces, they have attributes and methods that you expect to be there.

I'd agree that interfaces are something that exists in your mind and the documentation and not in the code as an object.