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std::enable_shared_from_this<T>::operator=

enable_shared_from_this<T>& operator=( const enable_shared_from_this<T> &obj ) noexcept;

Does nothing; returns *this.

Parameters

obj - an enable_shared_from_this to assign to *this

Return value

*this

Notes

The private std::weak_ptr<T> member is not affected by this assignment operator.

Example

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

#include <memory>
#include <iostream>

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() << std::endl;
}
Result
4

std::enable_shared_from_this<T>::operator=

enable_shared_from_this<T>& operator=( const enable_shared_from_this<T> &obj ) noexcept;

Does nothing; returns *this.

Parameters

obj - an enable_shared_from_this to assign to *this

Return value

*this

Notes

The private std::weak_ptr<T> member is not affected by this assignment operator.

Example

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

#include <memory>
#include <iostream>

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() << std::endl;
}
Result
4