What are good practice for forward declaration of nlohmann::json in C++?...

Error when repeating forward declaration with default template argument...

Forward headers for STL containers...

"Implicit instantiation of undefined template" when forward declaring template class...

Forward declaration of a namespaced C++ class in in Objective C...

Can one forward-declare a function taking a vector of incomplete type with a default value?...

Forward declaration of nested types/classes in C++...

C++ Forward declare using directive...

C++: Unknown pointer size when forward declaring (error C2036)...

May I #include in .hpp files?...

Includes and classes in C++...

"using typedef-name ... as class" on a forward declaration...

Forward declaration / when best to include headers?...

What is a parameter forward declaration?...

Forward function declarations in a Bash or a Shell script?...

friend function template with default template argument...

C++ Forward Declaring a class?...

Forward-declaration of enum member of template-specialization - fails with GCC...

using C struct that is declared later...

How to pass ForwardRef as args to TypeVar in Python 3.6?...

Python avoid mypy fails when redefining a class from another class in mutual reference...

Elfutils library forward declaration error...

Incorrect return type allowed for forward declared function: Why is there no linker error here?...

Forward declaring an enum in C++...

How do I forward declare an inner class?...

Forward Declaration of variables/classes in std namespace...

is a class declaration before base-clause a valid forward declaration?...

Correct way to forward declare structs?...

Declare procedures prototypes in nim...

Forward Declaration (PIMPL) for External Libraries also used in Method Declarations?...