结构成员的默认值

Question

（我确定这个问题已经得到回答，我只是不确定用正确的词来问它。如果有人能告诉我正确的术语是什么真棒！）

我正在用 C++ 为数据结构 class 实现 HashSet，我对结构的 C++ 语法有疑问。这是我的代码：

struct HashNode
{
    T value;
    HashNode* next = nullptr;
};

当调用 new HashNode 时，此代码能否正确地将 next 指针初始化为 nullptr？如果不是，new HashNode之后的next的值是多少？

Answer 1

Will this code correctly initialize the next pointer to nullptr when new HashNode is called?

是的，它将被初始化为nullptr。这是 in-class brace-or-equal initializer (default member initializer) (C++11 起)，如果在成员初始值设定项列表中省略成员，将使用它。

Through a default member initializer, which is simply a brace or equals initializer included in the member declaration, which is used if the member is omitted in the member initializer list

If a member has a default member initializer and also appears in the member initialization list in a constructor, the default member initializer is ignored.

结构成员的默认值

Default value of a struct member

c++

initialization

initializer

c++11