Comment by pacala | Hacker News Reader

Comment by pacala | Hacker News Reader

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There are 4 mainstream programming styles:

* Data Oriented Programming. There is data, and there are functions operating on the data.

* Functional Programming. Variant of DOP, with a strong emphasis on purism and abstract algebra concepts.

* Procedural Programming. Variant of DOP, lacking language level mechanisms or best practices around polymorphic interfaces. Largely obsolete.

* Object Oriented Programming. Everything is an object.

Information hiding and polymorphism are readily available in all styles, except PP. The trouble with OOP is that insists on two big lies:

* Everything is an object, therefore data is an object, therefore data must be hidden. In fact, data simply 'is' and you can't hide it. Think JSON. There is nothing to hide.

* Everything is a polymorphic object, codified as the popular 'Open/Closed Principle'. In fact, most code is functions that just compute some data. Never needs N different polymorphic variants. If the business cases ever warrant such variants, simply refactor a polymorphic interface into the code base.

I don't see any difference between DOP and procedural. Saying the difference is best practices and something vague about language mechanisms is accute to saying procedural is different to DOP because people say "do it good". This is even more formless than the criticism of no hard definitions levied against OOP by the same people.

The technical difference is lack of language-level module support, requiring manual management of vtables. It can be done, see Linux kernel for an example, but often times degenerates in a ball of globals.

To further clarify, one can use DOP style in many languages, including languages that are ostensibly OO. DOP is a style, using data hiding and polymorphism as sparingly as possible, as opposed to OOP style, which strongly encourages using data hiding and polymorphism at every corner.

Okay so it just sounds to me like careful OOP. Discipline just isn't a paradigm. It's an ethic and it's a good ethic. I love OOP, I've always built systems I was proud of with it. But to do that effectively you do need discipline and you need experience in design. Which most people think they can just skirt blindly by writing procedural code in class wrappers and the system will just magically emerge. This results in even more horrific programs when combined with blind TDD. This has always been nonsense. I don't use much OOP nowadays due to my work prioritizing efficiency and speed. Which OOP fails at miserably. But every now and again I'll find myself doing some monomorphism that looks like vtable dispatch without ever touching heap. And I'll kindly look back on my OOP days.

Agreed. Careful/Restrained OOP / 95% FP [the ML branch] / DOP, all names for the same sweet spot. The push back is against hard OOP culture, rooted in confused thinking.

* Everything is emphatically NOT an object. There is immutable data, there are functions and there are modules. These are not the interchangeable, learn to use them in the proper context.

* Everything is emphatically NOT a message. There are plain functions, there are polymorphic functions, there are RPCs and there are async messages. These are not interchangeable, learn to use them in the proper context.

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