Some weird bug in C++ | Together C & C++ | Page 1

astral agate Nov 20, 2022, 12:10 AM

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Something is going on, and I don't know what.

Compiler : Clang
Version : C++20

proven gustBOT Nov 20, 2022, 12:10 AM

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astral agate Nov 20, 2022, 12:11 AM

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Also this

misty dome Nov 20, 2022, 12:12 AM

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std::function<void()>

astral agate Nov 20, 2022, 12:12 AM

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Same thing lol

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I have tried anything

misty dome Nov 20, 2022, 12:12 AM

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does it compile though, could just be bad intellisense

astral agate Nov 20, 2022, 12:12 AM

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Should compile but I get another error

gloomy ice Nov 20, 2022, 12:13 AM

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astral agate Should compile but I get another error

show the compile error

astral agate Nov 20, 2022, 12:13 AM

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error: /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.3.sdk/usr/include/c++/v1/stdlib.h:143:10: error: no member named 'ldiv' in the global namespace; did you mean simply 'ldiv'?
  return ::ldiv(__x, __y);
         ^~
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.3.sdk/usr/include/stdlib.h:149:9: note: 'ldiv' declared here
ldiv_t   ldiv(long, long) __pure2;
         ^
In file included from Source/Modules/Core/Surface.cpp:1:
In file included from Source/Modules/Core/../Imported/FFI.hpp:5:
In file included from /usr/local/include/SDL2/SDL.h:32:
In file included from /usr/local/include/SDL2/SDL_main.h:25:
In file included from /usr/local/include/SDL2/SDL_stdinc.h:46:
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.3.sdk/usr/include/c++/v1/stdlib.h:148:10: error: no member named 'lldiv' in the global namespace; did you mean simply 'lldiv'?
  return ::lldiv(__x, __y);
         ^~
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.3.sdk/usr/include/stdlib.h:153:10: note: 'lldiv' declared here
lldiv_t  lldiv(long long, long long);

misty dome Nov 20, 2022, 12:14 AM

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thonk

gloomy ice Nov 20, 2022, 12:15 AM

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you're intermediate so you probably alr know this, but your compiler error is always more accurate than intellisense

ruby tundra Nov 20, 2022, 12:15 AM

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sounds like the mac dev experience

astral agate Nov 20, 2022, 12:15 AM

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I have a suspicion that this is an error because SDL is a C library which I tried to import within a namespace

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So that I have a separate namespace for every library in C that I use if so

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So that there is nothing like a possible function name overlap

ruby tundra Nov 20, 2022, 12:16 AM

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well

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SDL is not header only

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I can only guess problems will happen if you try to link against it

amber needle Nov 20, 2022, 12:17 AM

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what if you remove the global namespace before calls

astral agate Nov 20, 2022, 12:17 AM

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Do I have to use Boost's library for dynamic linking now... oh god

ruby tundra Nov 20, 2022, 12:17 AM

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just don't put C libraries in their own namespace ™️

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if there was naming collision the linker will know

astral agate Nov 20, 2022, 12:18 AM

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Alright I will try something then

ruby tundra Nov 20, 2022, 12:19 AM

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also I wish we could actually do something like this
separating libraries into namespaces

astral agate Nov 20, 2022, 12:20 AM

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The namespace isn't a problem

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The error persists

ruby tundra Nov 20, 2022, 12:21 AM

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did you perhaps ever have a using line anywhere in headers

astral agate Nov 20, 2022, 12:21 AM

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only in the first one

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for Core.h

hazy linden Nov 20, 2022, 12:22 AM

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I suppose it might work if you do like namespace lolol { extern "C" { #include <lib.h> } }? 😄

astral agate Nov 20, 2022, 12:22 AM

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using Element = std::function<void()>;

ruby tundra Nov 20, 2022, 12:22 AM

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okay so no using namespace

astral agate Nov 20, 2022, 12:22 AM

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astral agate `using Element = std::function<void()>;`

Theoretically, I can even do typedef

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But I prefer this

ruby tundra Nov 20, 2022, 12:23 AM

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i heard typedef and templates dont play well

astral agate Nov 20, 2022, 12:23 AM

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yeah

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so I went with using

astral agate Nov 20, 2022, 12:23 AM

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hazy linden I suppose it might work if you do like `namespace lolol { extern "C" { #include ...

Good point I will try

hazy linden Nov 20, 2022, 12:23 AM

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there's probably still a million ways that can go wrong

ruby tundra Nov 20, 2022, 12:24 AM

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also iirc doesn't SDL already wrap itself with #ifdef __cplusplus so that's not needed?

astral agate Nov 20, 2022, 12:25 AM

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I think it does, but I did it anyways

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and... same error

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lol

hazy linden Nov 20, 2022, 12:25 AM

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¯_(ツ)_/¯

astral agate Nov 20, 2022, 12:26 AM

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My Window.cpp file gets no errors when I use std::vector

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but doing this with Surface.cpp gives me errors

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how come

hazy linden Nov 20, 2022, 12:26 AM

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core.hpp
__CORE_H_
thonk

ruby tundra Nov 20, 2022, 12:26 AM

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sus

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also what's in FFI.hpp

hazy linden Nov 20, 2022, 12:26 AM

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also __ is reserved 😛

astral agate Nov 20, 2022, 12:27 AM

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So I should remove the guards?

ruby tundra Nov 20, 2022, 12:27 AM

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no

astral agate Nov 20, 2022, 12:27 AM

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I learned this from CLion as it does this automatically

hazy linden Nov 20, 2022, 12:27 AM

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just the double underscores 😄

ruby tundra Nov 20, 2022, 12:27 AM

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just don't use double underscore

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yea

ruby tundra Nov 20, 2022, 12:27 AM

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astral agate I learned this from CLion as it does this automatically

adding UB to your code one header guard at a time

hazy linden Nov 20, 2022, 12:27 AM

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underscore followed by capitcal letter is also reserved, IIRC

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and anything with a leading underscore in the global namespace?

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(not that I'd expect this to be the actual problem)

ruby tundra Nov 20, 2022, 12:29 AM

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ruby tundra also what's in FFI.hpp

this might be the trouble maker

astral agate Nov 20, 2022, 12:29 AM

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ruby tundra this might be the trouble maker

#ifndef _H_FFI
#define _H_FFI

namespace Droplet::FFI
{
namespace SDL
{
extern "C" { 
    #include <SDL2/SDL.h>
}
} // namespace SDL
} // namespace Droplet::FFI

#endif

ruby tundra Nov 20, 2022, 12:31 AM

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and how are you using SDL in surface.cpp?

astral agate Nov 20, 2022, 12:31 AM

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#include "../Imported/FFI.hpp"
#include "core.hpp"

#include <memory>
#include <vector>

namespace Droplet
{
class Surface
{
private:
    Window* m_Owner{};
    std::vector<Element> m_Elements{};

public:
    Surface()
    {
        m_Owner = nullptr;
    }

    explicit Surface(Window &refOwner)
    {
        m_Owner = &refOwner;
    }

    ~Surface() {
        delete m_Owner;
    };
};

} // namespace Droplet

Still no SDL calls

hazy linden Nov 20, 2022, 12:34 AM

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I'd imagine maybe SDL includes some C stdlib header which includes a combined C / C++ stdlib header which breaks something somehow somewhere?

astral agate Nov 20, 2022, 12:34 AM

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Do I have to look for a C++ wrapper of SDL now...

ruby tundra Nov 20, 2022, 12:35 AM

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I have a guess

astral agate Nov 20, 2022, 12:35 AM

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yes?

ruby tundra Nov 20, 2022, 12:35 AM

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hazy linden I'd imagine maybe SDL includes some C stdlib header which includes a combined C ...

wait he mentioned it lol

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so the solution to this would be include the headers before SDL

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or just include SDL normally man

astral agate Nov 20, 2022, 12:36 AM

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WHAT

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I INCLUDED BEFORE

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AND IT WORKS

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wtf

ruby tundra Nov 20, 2022, 12:37 AM

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?

astral agate Nov 20, 2022, 12:37 AM

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okay this is strange

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No error on this

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I moved core.hpp on the top

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Okay, but why is this ?

ruby tundra Nov 20, 2022, 12:37 AM

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hmmmm

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whats in core?

astral agate Nov 20, 2022, 12:38 AM

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#ifndef _CORE_H
#define _CORE_H

#include <functional>

namespace Droplet
{
using Element = std::function<void>;

class Window
{
};
class Surface
{
};

} // namespace Droplet

#endif // _CORE_H

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And suddently

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std::function

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is also working

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when i moved this shit

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what the fuck

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This is cursed

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Wait so

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Okay

hazy linden Nov 20, 2022, 12:38 AM

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oh, I have an idea

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scrolling through a few SDL headers, it looks like they forward declare some external stuff

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that might break when it's now in namespace SDL

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hence the errors about "lol what's ::whatever, did you mean whatever"

astral agate Nov 20, 2022, 12:39 AM

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error: /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.3.sdk/usr/include/c++/v1/math.h:792:91: error: no member named 'acosf' in the global namespace; did you mean simply 'acosf'?
inline _LIBCPP_INLINE_VISIBILITY float       acos(float __lcpp_x) _NOEXCEPT       {return ::acosf(__lcpp_x);}
                                                                                          ^~
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.3.sdk/usr/include/math.h:308:14: note: 'acosf' declared here
extern float acosf(float);
             ^
In file included from Source/Modules/Core/Surface.cpp:2:
In file included from Source/Modules/Core/../Imported/FFI.hpp:9:
In file included from /usr/local/include/SDL2/SDL.h:32:
In file included from /usr/local/include/SDL2/SDL_main.h:25:
In file included from /usr/local/include/SDL2/SDL_stdinc.h:90:
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.3.sdk/usr/include/c++/v1/math.h:793:91: error: no member named 'acosl' in the global namespace; did you mean simply 'acosl'?
inline _LIBCPP_INLINE_VISIBILITY long double acos(long double __lcpp_x) _NOEXCEPT {return ::acosl(__lcpp_x);}
                                                                                          ^~
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.3.sdk/usr/include/math.h:310:20: note: 'acosl' declared here
extern long double acosl(long double);
                   ^
  > in Source/Modules/Core/Surface.cpp

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Another error now

ruby tundra Nov 20, 2022, 12:40 AM

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yeah so basically same thing as before

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withered

astral agate Nov 20, 2022, 12:40 AM

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What if I remove the FFI namespace

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and just use SDL normally

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let's see if that works

hazy linden Nov 20, 2022, 12:40 AM

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that should be fine

astral agate Nov 20, 2022, 12:40 AM

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if it works, then whatever

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SDL names are prefixed with SDL_

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so I don't care as much

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wait hold up

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I saw

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the error was

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because i had this

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and then I did

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I guess include order matters

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lol

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so yay, I can have namespaces

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coolio

hazy linden Nov 20, 2022, 12:43 AM

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still very cursed

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you now probably have copies of those inline cmath functions in SDL:: 😄

astral agate Nov 20, 2022, 12:43 AM

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This is the error I get now, but I know the problem.

[ 20%]: cache compiling.release Source/Modules/Core/Window.cpp
[ 20%]: cache compiling.release Source/Modules/Core/Surface.cpp
error: Source/Modules/Core/Surface.cpp:9:7: error: redefinition of 'Surface'
class Surface
      ^
Source/Modules/Core/core.hpp:13:7: note: previous definition is here
class Surface
      ^
1 error generated.
  > in Source/Modules/Core/Surface.cpp

ruby tundra Nov 20, 2022, 12:43 AM

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average experience of trying to tame C

astral agate Nov 20, 2022, 12:44 AM

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I hate writing header files

hazy linden Nov 20, 2022, 12:44 AM

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it's not wrong

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you can't define the class twice, differently

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did you want those in core.hpp to be forward declarations?

astral agate Nov 20, 2022, 12:45 AM

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hazy linden you can't define the class twice, differently

Yes I know, I had just done class Something {}; instead of class Something;

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And now I realised

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I have to make a prototype of every fucking function in the class

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Because I get this (since the type is incomplete, as there are no declarations in the header)

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Is there a way to automake headers?

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Or is it always hand by hand?

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Meanwhile I swapped to smart pointers.

ruby tundra Nov 20, 2022, 12:52 AM

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iirc you need to tell unique_ptr the destructor you want it to use if it's not just freeing memory

astral agate Nov 20, 2022, 12:52 AM

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It's just freeing memory in this case

ruby tundra Nov 20, 2022, 12:53 AM

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ohh okay

astral agate Nov 20, 2022, 12:53 AM

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Because Window has its own destructor

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    ~Window()
    {
        FFI::SDL::SDL_DestroyWindow(s_windowHandle);
    }

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Btw, if you find my naming conventions weird

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s_ means state
m_ means member

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Like this from my settings.hpp

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Thanks a lot for the help everyone 🙂

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!close

#Some weird bug in C++