c++ - 如何禁止对象的构造？

Question

如何禁止对象的构造？我标记= delete;所有相关的特殊功能如下:

struct A
{
    A() = delete;
    A(A const &) = delete;
    A(A &&) = delete;
    void * operator new(std::size_t) = delete;
    void operator delete(void *) = delete;
};
A x{};
A y = {};
A * z = ::new A{};

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但是x、y 和*z 仍然可以存在。该怎么办？我对这两种情况都感兴趣；静态/堆栈分配和堆分配。

Answer 1

一个选择是给类一个纯虚函数，并将其标记为final:

struct A final
{
  virtual void nonconstructible() = 0;
};

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