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std::enable_shared_from_this<T>::operator=

enable_shared_from_this&
    operator=( const enable_shared_from_this &rhs ) noexcept;
(since C++11)
(constexpr since C++26)

Does nothing: weak_this is not affected by the assignment.

Parameters

rhs - another enable_shared_from_this to assign to *this

Return value

*this

Notes

operator= is defined as protected in order to prevent accidental slicing but allow derived classes to have default assignment operators.

Example

#include <iostream>
#include <memory>
 
class SharedInt : public std::enable_shared_from_this<SharedInt>
{
public:
    explicit SharedInt(int n) : mNumber(n) {}
    SharedInt(const SharedInt&) = default;
    SharedInt(SharedInt&&) = default;
    ~SharedInt() = default;
    
    // Both assignment operators use enable_shared_from_this::operator=
    SharedInt& operator=(const SharedInt&) = default;
    SharedInt& operator=(SharedInt&&) = default;
    
    int number() const { return mNumber; }
    
private:
    int mNumber;
};
 
int main()
{
    std::shared_ptr<SharedInt> a = std::make_shared<SharedInt>(2);
    std::shared_ptr<SharedInt> b = std::make_shared<SharedInt>(4);
    *a = *b;
    
    std::cout << a->number() << '\n';
}

Output:

4

See also

shared_ptr
(C++11)
smart pointer with shared object ownership semantics
(class template)

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Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
https://en.cppreference.com/cpp/memory/enable_shared_from_this/operator%3D

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