std::enable_shared_from_this<T>::enable_shared_from_this

 

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std::enable_shared_from_this

Protected member functions

enable_shared_from_this::enable_shared_from_this

enable_shared_from_this::~enable_shared_from_this

enable_shared_from_this::operator=

Public member functions

enable_shared_from_this::shared_from_this

enable_shared_from_this::weak_from_this (C++17)

 

constexpr enable_shared_from_this() noexcept;	(1)	(since C++11)
enable_shared_from_this( const enable_shared_from_this& other ) noexcept;	(2)	(since C++11)

Constructs a new enable_shared_from_this object. weak_this is value-initialized.

Parameters

other

-

an enable_shared_from_this to copy

Notes

There is no move constructor: moving from an object derived from enable_shared_from_this does not transfer its shared identity.

Example

Run this code

#include <memory>
 
struct Foo : public std::enable_shared_from_this<Foo>
{
    Foo() {} // implicitly calls enable_shared_from_this constructor
    std::shared_ptr<Foo> getFoo() { return shared_from_this(); }
};
 
int main()
{
    std::shared_ptr<Foo> pf1(new Foo);
    auto pf2 = pf1->getFoo(); // shares ownership of object with pf1
}

See also

shared_ptr (C++11)

smart pointer with shared object ownership semantics (class template)