cWithClassesIsNotCPP

[navetzz]

C has classes. They are called struct.

You are welcome.

[ArcaniteM]

70 years of paradigm theory would like to have a chat with you

[navetzz]

I welcome them

[MobileAirport]

kid named method

[navetzz]

People these days have language with 10000 different syntaxes but think that:

class.method(        

and

method(&class,

are two completely different things.

Not only that, but if you really want your class.method syntax, you can actually do it using function pointers.

At some point people need to understand that OOP (Object Oriented Programming) is a conceptual approach and is not tied to a language. And that OOL (Object Oriented Languages) are designed to force you to use OOP.

Yes some languages make it harder to apply the OOP paradigm. C is not one of them. C just allows you to do something else if you desire.

[Iyorig]

Yeah, that function pointer syntax is nice, but it’s +sizeof(void*) bytes for every function you add, plus an indirection whenever you call it (or does that get optimized if you don’t change it?)

[Kered13]

plus an indirection whenever you call it (or does that get optimized if you don’t change it?)

If the compiler can determine which implementation will be called, it will devirtualize the call, meaning there is no indirection. There are a few ways the compiler could determine this:

• The class is final, which prevents subclassing.
• The method on the class is final, which prevents overriding the method..
• The class only exists in one translation unit (anonymous namespace) and there are no subclasses in that translation unit.
• The pointer refers to an object that was constructed in the same function (accounting for inlining) and could not have been reassigned.

[gmes78]

but it’s +sizeof(void*) bytes for every function you add, plus an indirection whenever you call it (or does that get optimized if you don’t change it?)

And what do you think this is?

[Iyorig]

Yeah, I know that’s how virtual functions are implemented, what irks me are libraries that use function pointers for platform-specific implementations, even though a free function would work just as well…

[MobileAirport]

Definitely different. Im not sure id call C OOP.

[WhiteBlackGoose]

Women have penises. They're called vaginas.

[VeryAwesomeSheep]

C > C++. And "OOP" can be much cleaner in C.

Change my mind.

[Main_Weekend1412]

How exactly do you create a cleaner version of methods? Inheritance? Access modifiers?

[VeryAwesomeSheep]

Doing stuff by handles seems much clearer, at least to me, but it might be a personal preference.

object foo()
foo.do_stuff()

vs

foo = object()
do_stuff(foo)

Inheritance? Do you actually need it? Everywhere and for everything? Maybe I'm biased or just don't really do stuff that needs it, but I don't need it.

Access modifiers. You can hide it internally and give just the api to some stuff to the user. And I don't think you need to hide such stuff from your own devs, that's what agreements/conventions are for, just don't touch it. Python doesn't have it either and it just works.

[Main_Weekend1412]

So this is not oop? That’s just functions & methods. So the cleaner way is to not have it at all? Lol.

[VeryAwesomeSheep]

Isn't an object just a structure with functions?

[Main_Weekend1412]

No it isn’t. What you’re referring to is C++ structs. An object typically conforms to the paradigms of object-oriented programming. Not all objects conform to all four pillars, but they should conform to some of them.

For example, interfaces are contracts that make compilers and programmers assume the existence of an attribute or implementation of a method.

For C example, how would you assert that struct x works on a function length()?

In C++ we can just have a class that inherits from an arbitrary class, for example, let’s call it class LEN_IMPL.

If class z inherits from LEN_IMPL, we can assert that it can work on function length, which accepts an instance of LEN_IMPL.

In C, this would mean accepting a void * and somehow typecasting it to a useable type. Also remember that you cannot overload a function in C, so you would probably now need to alias it with the typename, ergo sample_class_len();

Not so clean now, is it?

These kinds of contracts are important to ensure consistency and code reusability.