c++ - 使用 placement new 时删除它的替代方法

Question

我读了here那个

As long as you’re careful, it’s okay (not evil) for an object to commit suicide (delete this).

Here’s how I define “careful”:

You must be absolutely 100% positively sure that this object was allocated via new (not by new[], nor by placement new, nor a local object on the stack, nor a namespace-scope / global, nor a member of another object; but by plain ordinary new).

如果我使用 placement new，我有什么选择？

Answer 1

Placement new 用于分隔内存分配和对象生命周期，因此您通常会显式调用析构函数:

myobj->~myclass();

稍后释放内存，或继续将内存用于其他目的。