std::enable_shared_from_this<T>::enable_shared_from_this

From cppreference.com
 
C++
 
Utilities library
Type support (basic types, RTTI, type traits)
Dynamic memory management
Error handling
Program utilities
Variadic functions
Library feature-test macros
Date and time
Function objects
(C++11)
(C++11)
(C++14)
Relational operators (deprecated in C++20)
Comparisons (C++20)
Common vocabulary types
(C++11)
(C++17)
(C++17)
(C++17)
(C++17)
(C++17)

Swap, forward and move
(C++14)
(C++11)
(C++11)
(C++11)
Elementary string conversions
(C++17)
(C++17)
(C++17)
Type operations
(C++11)
(C++17)
(C++17)
 
Dynamic memory management
Uninitialized storage
(C++17)
(until C++20)
(until C++20)
(until C++20)
Garbage collection support
(C++11)
(C++11)
(C++11)
(C++11)
(C++11)
(C++11)
Miscellaneous
(C++11)
(C++20)
(C++11)
(C++11)
(C++20)
C Library
Low level memory management
 
std::enable_shared_from_this
Protected member functions
enable_shared_from_this::enable_shared_from_this
Public member functions
(C++17)
 
constexpr enable_shared_from_this() noexcept;
 (1) (since C++11)
enable_shared_from_this( const enable_shared_from_this<T>&obj ) noexcept;
 (2) (since C++11)

Constructs a new enable_shared_from_this object. The private std::weak_ptr<T> member is value-initialized.

Parameters

obj - an enable_shared_from_this to copy

Notes

There is no move constructor: moving from an object derived from 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

(C++11)
 smart pointer with shared object ownership semantics
(class template)
Retrieved from "https://en.cppreference.com/mwiki/index.php?title=cpp/memory/enable_shared_from_this/enable_shared_from_this&oldid=93923"