Comments on: Polymorphism: Part 1

By: Mario Pareja

Mario Pareja — Wed, 13 Mar 2013 14:41:00 +0000

Now that everyone is hopefully done commenting on your “IWhatever” naming style, I’d like to ask a simple question. What were some of those other things you felt you _did_ learn that you wouldn’t otherwise be exposed to?

By: Reading Notes 2013-03-04 | Matricis

Reading Notes 2013-03-04 | Matricis — Mon, 04 Mar 2013 18:24:20 +0000

[...] Polymorphism: Part 1 (John Teague) – Great tutorial that explains an important concept in programmation. [...]

By: John Teague

John Teague — Fri, 01 Mar 2013 15:41:00 +0000

My development style is more composition than inheritance, so it was just easier for me to make the examples like this. the ISendMessages interface could have easily been an abstract class (I’m hoping to get to an example where it has one). Then the inheritance tree would start from a class. To me however, if you look at how I defined polymorphism, where you have different behavior with a consistent keeping a consistent contract, it doesn’t matter if you start from a base class or an interface.

The important part is to use the abstraction, not the concrete implementation. Whether the abstraction is an interface or class you get the same benefits.

HTH,
John

By: Dbr

Dbr — Fri, 01 Mar 2013 13:09:00 +0000

Typo – I meant to say “What is it about it that makes it polymorphism?”…

By: Dbr

Dbr — Fri, 01 Mar 2013 13:07:00 +0000

Hi. Sorry if this is a little basic, but can you just quickly define “polymorphism” as opposed to “inheritance”? I see the benefit of the way you have written your code, I don’t need help with that, but I would just call that a good example of inheriting from an interface? What is it about it that makes it inheritance?

By: Carlos Ribas

Carlos Ribas — Tue, 26 Feb 2013 17:17:00 +0000

NServiceBus is full of self-contradictions with regards to this “new style” interface naming. IHandleMessages simply aliases the traditionally-named IMessageHandler. There’s ISpecifyMessageHandlerOrdering and then there’s IMessageCreator (not ICreateMessages?).

This strikes me as ridiculous. If programming were a democracy I’d vote for the “let’s stop with the cute English-y stuff” party.

By: Nathan Alden

Nathan Alden — Tue, 26 Feb 2013 17:11:00 +0000

Your intent is misplaced and contradicts decades of usage patterns. Additionally, it’s factually wrong. An interface does nothing. It merely represents that which does something.

By: Nathan Alden

Nathan Alden — Tue, 26 Feb 2013 17:07:00 +0000

ISendMessages? No you don’t. You’re an interface; you represent that which sends messages. IMessageSender is much more accurate. Please, let’s all stop trying to make C# (and other similar languages) read like English; it’s infantile.

By: Matthew Roberts

Matthew Roberts — Tue, 26 Feb 2013 06:13:00 +0000

John, its an interesting POV. I personally am not used to this way mainly because the .NET community are well attuned to using singular nouns for object naming (following Microsoft best practises of course!).

I recently started learning Objective-C and was surprised to see many objects names were verbs.

But at the end of the day, the compiler wont argue with you – only us humans will =]

By: John Teague

John Teague — Tue, 26 Feb 2013 05:08:00 +0000

That was a typo on my part, it should have been OrderProcessor to be consistent with the examples