error C2027: use of undefined type 'CEntity' (compiling source file StateLoad.cpp)c:\users\olli-\documents\workspace\gunhero\gunheroremake\level.h(30): note: see declaration of 'CEntity' (compiling source file StateLoad.cpp)c:\program files (x86)\microsoft visual studio\2017\community\vc\tools\msvc\14.15.26726\include\memory(2081): note: while compiling class template member function 'void std::default_delete<_Ty>::operator ()(_Ty *) noexcept const with [_Ty=CEntity]' (compiling source file StateLoad.cpp)c:\program files (x86)\microsoft visual studio\2017\community\vc\tools\msvc\14.15.26726\include\memory(2296): note: see reference to function template instantiation 'void std::default_delete<_Ty>::operator ()(_Ty *) noexcept const with [_Ty=CEntity]' being compiled (compiling source file StateLoad.cpp)c:\program files (x86)\microsoft visual studio\2017\community\vc\tools\msvc\14.15.26726\include\memory(2132): note: see reference to class template instantiation 'std::default_delete<_Ty> with [_Ty=CEntity]' being compiled (compiling source file StateLoad.cpp)c:\program files (x86)\microsoft visual studio\2017\community\vc\tools\msvc\14.15.26726\include\memory(2179): note: see reference to class template instantiation 'std::_Unique_ptr_base<_Ty,_Dx> with [_Ty=CEntity, _Dx=std::default_delete<CEntity>]' being compiled (compiling source file StateLoad.cpp)c:\users\olli-\documents\workspace\gunhero\gunheroremake\levelentitydata.h(18): note: see reference to class template instantiation 'std::unique_ptr<CEntity,std::default_delete<_Ty>> with [_Ty=CEntity]' being compiled (compiling source file StateLoad.cpp)