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0 pointspdkl9511y ago0 comments

I suspect some of the problems that many people have with OO tend originate from the C++ and relate languages such as Java. These languages aren't really OO in the Alan Kay sense of the term[1]. They are languages with classes, polymorphic inheritance, and object style binding of methods to structures, but they do not feature "everything is an object with message passing".

By comparison, you really see a lot more of the utility of OO in languages smalltalk or possibly ruby[2] where you can extend everything. I know tend to write my ruby (despite it being a multi-paradigm language) in a manner that you describe: FP style with objects hiding the details.

Of course, all of these languages have their strengths and weaknesses and OO isn't useful for everything. I just think OO has gotten a bit of a bad reputation from some of the languages that chose to label themselves OO even when their implementation was only superficial. This bad reputation may lead to dismissal of the whole idea, producing the false dichotomy you mention.

Incidentally, the lack of strict OO (or any language style) in ruby is what I really like about the language. You can be strict OO if you want, but you can also use classic (C-style) imperative programing when it makes more sense (or FP, or whatever).

[1] http://c2.com/cgi/wiki?AlanKaysDefinitionOfObjectOriented

[2] Regrettably, OCaml is one of those languages that is still in my "looks interesting, I should learn that" queue, so I cannot speak to how it implements OO.

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colanderman11y ago

OCaml's OO is IMHO not very interesting, beside the concept of "functional objects", which really ought to exist without the rest of the Java-style OO baggage. (Briefly: methods can easily return a copy of an object with some fields modified; and anonymous, structurally typed objects may be constructed.) Otherwise it is standard Java/C++ fare (albeit more streamlined and with better typing).

On the other hand, OCaml is worth learning for the module+type system alone. Every other language could benefit from its ideas; the only language I've seen that's comparable is Coq (which bases its module system on OCaml's). (And the module and type system really work in tandem: there are advanced mechanisms for type structure hiding that aid forward compatibility.)