[SOLVED] Forward Declarations and SharedPtr's

I’m currently in the middle of refactoring my project, I have a lot of c++ classes that reference each other and want to strictly use forward declarations in my header files.

In short - is this a valid structure:


class ReferenceClass;
class MyClass {
void DoThingsWithRef();
SharedPtr<ReferenceClass> pRef;


void MyClass::DoThingsWithRef()

I Keep Getting Compile Errors:

2>c:\urho3d-1.7\build\include\urho3d\core\../Container/Ptr.h(223): error C2027: use of undefined type 'GridGeographicData'
2>c:\users\casht\repos\greatgame\GridWorld.h(15): note: see declaration of 'GridGeographicData'
2>c:\urho3d-1.7\build\include\urho3d\core\../Container/Ptr.h(220): note: while compiling class template member function 'void Urho3D::SharedPtr<GridGeographicData>::ReleaseRef(void)'
2>c:\urho3d-1.7\build\include\urho3d\core\../Container/Ptr.h(79): note: see reference to function template instantiation 'void Urho3D::SharedPtr<GridGeographicData>::ReleaseRef(void)' being compiled
2>c:\users\casht\repos\greatgame\Grid.h(93): note: see reference to class template instantiation 'Urho3D::SharedPtr<GridGeographicData>' being compiled
2>c:\urho3d-1.7\build\include\urho3d\core\../Container/Ptr.h(223): error C2227: left of '->ReleaseRef' must point to class/struct/union/generic type

Ensure that your class’ destructor is defined in the cpp.


Solved - This was part of the problem, also the SharedPtr do indeed work with forward declarations.

SharedPtr could work with incomplete type unless reference counter is used.
So, construction, destruction (including member destruction), assignment and copying of shared ptrs require complete type.

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