handle.hpp

#pragma once
 
#include <type_traits>
#include <utility>
 
namespace plugify {
    template<typename T>
    class Handle {
    public:
        Handle() noexcept : _impl{nullptr} {}
 
        Handle(T& impl) noexcept : _impl{&impl} {}
 
        Handle(const Handle&) = default;
        Handle(Handle&&) = default;
 
 #if __cpp_impl_three_way_comparison
        auto operator<=>(const Handle&) const = default;
#endif // __cpp_impl_three_way_comparison
 
        Handle& operator=(const Handle&) & = default;
        Handle& operator=(const Handle&) && = delete;
        Handle& operator=(Handle&&) & = default;
        Handle& operator=(Handle&&) && = delete;
 
        explicit operator bool() const noexcept {
            return _impl != nullptr;
        }
 
        operator uintptr_t() const noexcept {
            return reinterpret_cast<uintptr_t>(_impl);
        }
 
        operator void*() const noexcept {
            return (void*) _impl;
        }
 
    protected:
        T* _impl; 
    };
}