owner_before() 理解了aliasing constructor之后,shared_pointer::owner_before()就更好理解了;(参考https://www.zhihu.com/question/24816143) 在标准库的shared_ptr中,operator<,比较的是stored pointer,因此上面举例的那种情况,p9和obj两个shared_ptr是不相等的;而owner_before()是基于owner pointer的比较,因此p9...
让你好好体会一下，“The object does not own p ”意思：// shared_ptr constructor example#include...
share_ptr 的 aliasing constructor: 可以使得share_ptr 拥有某个对象控制权的时候,存储指针(storage pointer,shared_ptr 还有一个概念叫owned ptr 指向存储当前控制对象相关信息)指向另外一个对象,模板如下: template <class U> shared_ptr (const shared_ptr<U>& x, element_type* p) noexcept; 该构造函数是的...
share_ptr 的 aliasing constructor: 可以使得share_ptr 拥有某个对象控制权的时候,存储指针(storage pointer,shared_ptr 还有一个概念叫owned ptr 指向存储当前控制对象相关信息)指向另外一个对象,模板如下: template <class U> shared_ptr (const shared_ptr<U>& x, element_type* p) noexcept; 该构造函数是的...
Issue description A returned std::shared_ptr created via the "aliasing constructor" gets lost when the class inherits from std::enable_shared_from_this. I've tracked this down and it appears that class_::init_holder (variant 1) will use ...
_Ptr = nullptr; _Right._Rep = nullptr; } template <class _Ty2> void _Alias_move_construct_from(shared_ptr<_Ty2>&& _Other, element_type* _Px) noexcept { // implement shared_ptr's aliasing move ctor _Ptr = _Px; _Rep = _Other._Rep; _Other._Ptr = nullptr; _Other._Rep = ...
A shared_ptr may also own no objects, in which case it is called empty (an empty shared_ptr may have a non-null stored pointer if the aliasing constructor was used to create it). All specializations of shared_ptr meet the requirements of CopyConstructible, CopyAssignable, and LessThan...
8)Thealiasing constructor: constructs ashared_ptrwhich shares ownership information with the initial value ofr, but holds an unrelated and unmanaged pointerptr. If thisshared_ptris the last of the group to go out of scope, it will call the stored deleter for the object originally managed byr....
shared_ptr<_RawYp>(*this, const_cast<_RawYp*>(static_cast<const _Yp*>(__ptr))) 这个调用的是std::shared_ptr的别名构造函数(The aliasing constructor),意思是说,共享 r 参数的引用计数, 但是.get()返回的是 ptr 指针。 template< class Y > shared_ptr( const shared_ptr<Y>& r, element_ty...
A shared_ptr may also own no objects, in which case it is called empty (an empty shared_ptr may have a non-null stored pointer if the aliasing constructor was used to create it). All specializations of shared_ptr meet the requirements of CopyConstructible, CopyAssignable, and LessThanComp...