Why does your header file contain code?
this post was submitted on 22 Mar 2024
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It's not the case with this meme, but in C++ template definitions have to be defined in the headers if they're not full template specializations
Gonna go with... whoosh
The stone-age called, they want their languages that need header files back!
(I use Rust btw.)
I know that header files have some pretty horrible issues with templates and cyclic dependencies and so on, but from an organisational perspective I really like them. If I have to implement some complicated algorithm I could easily have a thousand likes + of Code, but the header still quite nicely shows the general structure in one or two screens. Whenever I do classes in python I start wishing for headers at like 300 lines, simply because I loose track of all the functions I already made.
Maybe I'm just not a good python programmer tho.
I'd say at 1000 lines it usually makes sense to extract some parts into other files. But sure, I guess most obscurities have positive aspects. On the other hand, nothing is stopping you from writing a separate file with only function signatures next to your python scripts. It's just not required, because why would it ;)
Why are you putting the implementation in the .h file? You're supposed to declare in the header and implement in the .cpp files. The meme is reversed
If C++/C were real languages for real programming they'd enforce this in the compiler.
No sane language designer would say "it is imperative that you do not implement your class in its header file" then write a compiler designer to say "oh you implemented your code in the header file? lol lmao that rocks"
They have played you all for fools.
I actually like how much freedom C++ gives you. As long as it is fed valid code, it does not give a fuck about how you choose to structure your project
That freedom becomes misery on the instant you have to start maintain the code from some other free spirit, whose style is totally different from yours.
Or the free spirit was actually you yourself but from three months ago
not saying it's good design, I ditched C++ long ago. at least the C++20 modules API is gonna fix this, right guys?
Header files aren't part of the C++ language at all.
Also mandatory "C++/C is not a language"
If C++/C were real languages for real programming they'd enforce unreadability in the compiler.
No sane language designer would say "It is imperative that you write the most unreadable code possible" then write a compiler that says "oh your code doesn't triple dereference pointers? lol lmao that rocks"
They have played you all for fools.
There is an issue with templated code where the implementation does have to be in the header as well, though that is not the case here. C++20 introduced modules which I guess were meant to sort out this mess, but it has been a rocky road getting them to be supported by compilers.
The reason is that header files are pretty much copy/pasted into your c files when you include them. so the code in them keeps getting recompiled for every c file, which drastically increases overall build times. If you only declare in the header and have one c file implementing the functions you compile them only once.
AI reply? That's the point they're trying to make. The implementation shouldn't be in the header file, but it is. Look at the image.
pretty sure the meme is about how the implementation looks ugly but using the implementation looks good because all the code is abstracted away. if it was like you said then why would they compare the code to the main.cpp
I got confused. I was referring to the top-level comment in this thread, but that was actually posted by you, so... I got turned around.
But yeah, sounds about right, that the meme could be referring to the horrors in the h file vs the clean cpp file. 😄
Yeah that's why you're supposed to use header guards... If you don't and include your header in multiple places your program straight up won't compile.
drastically increases overall build times
oh wow. from 0ms all the way up to 0ms. That's almost 1000 times faster wow.
truly spoken like someone who has never worked on a large C/C++ project
thank god
Looks like we've got a Java programmer here taking C++ for a spin.
Yep, first thing that comes to mind is that header only classes need to use inline functions.
Member functions that are defined within a class definition are implicitly inline
Ah I see now that I mixed it up with classless functions in a header.
I haven't codes anything in C++ for such a long time, I completely forgot how to.
It's horrible, I did pure C for years but now I have to code in C++11 or worst like C++17