Question

我从此构造函数中收到此错误

严重性代码描述项目文件行抑制状态错误
(active) E0289 no instance of constructor "std::unique_ptr<_Ty, _Dx>::unique_ptr [with _Ty=InputComponent, _Dx=std::default_delete<InputComponent>]" matches the argument list

代码：

    class GameWorldObject 
    {
    public:

    GameWorldObject::GameWorldObject(std::unique_ptr<GraphicsComponent> graphicsComponent, std::unique_ptr<LogicComponent> logicComponent, std::unique_ptr<InputComponent> inputComponent)
        :
        m_graphicsComponent( std::move(graphicsComponent) ), // ERROR
        m_inputComponent( std::move(logicComponent) ), // ERROR
        m_logicComponent( std::move(inputComponent) ) // ERROR
    {}



        // these auto initialize to null
        std::unique_ptr<GraphicsComponent> m_graphicsComponent;
        std::unique_ptr<LogicComponent> m_logicComponent;
        std::unique_ptr<InputComponent> m_inputComponent;

    };

我很傻，因为此示例对我有用，并且看起来与之前的示例相同：

    struct Animal {
        virtual ~Animal() {}
        virtual void speak() = 0;
    };


    struct Dog : Animal {
        void speak() override { std::cout << "Woof!\n"; }
    };

    std::unique_ptr<Animal> createPet() {
        return std::make_unique<Dog>();

    }

    class House {
    public:
        House(std::unique_ptr<Animal> pet) // seems identical
            :
            m_pet(std::move(pet)) // seems identical
        {}

        std::unique_ptr<Animal> m_pet; // seems identical
    };

    void main()
    {

        auto pet = createPet(6.0);
        pet->speak();

        House house(std::move(pet));

        //pet->speak(); err pet is nullptr
        house.m_pet->speak();
    }

这两者之间有什么区别？为什么前一个不起作用？

请注意，我尚未在InputComponent，GraphicsComponent或LogicComponent中实现任何类型的构造函数，析构函数或复制构造函数。

实际上，这是InputComponent

class InputComponent
{

};

使用std :: move在unique_pointers上初始化器列表中令人困惑的错误

0 个答案: