std::pair<T1,T2>::operator=

(1) 
pair& operator=( const pair& other );
 (until C++20) 
constexpr pair& operator=( const pair& other );
 (since C++20)
(2) 
template< class U1, class U2 >
pair& operator=( const pair<U1,U2>& other );
 (until C++20) 
template< class U1, class U2 >
constexpr pair& operator=( const pair<U1,U2>& other );
 (since C++20)
(3) 
pair& operator=( pair&& other ) noexcept(/* see below */);
 (since C++11)
(until C++20) 
constexpr pair& operator=( pair&& other ) noexcept(/* see below */);
 (since C++20)
(4) 
template< class U1, class U2 >
pair& operator=( pair<U1,U2>&& other );
 (since C++11)
(until C++20) 
template< class U1, class U2 >
constexpr pair& operator=( pair<U1,U2>&& other );
 (since C++20)

Replaces the contents of the pair.

1) Copy assignment operator. Replaces the contents with a copy of the contents of other.
2) Assigns other.first to first and other.second to second
3) Move assignment operator. Replaces the contents with those of other using move semantics.
4) Assigns std::forward<U1>(p.first) to first and std::forward<U2>(p.second) to second.

The behavior of these functions is undefined unless:

 (until C++17)

These functions do not participate in overload resolution (or, for the copy assignment operator, is defined as deleted) if any required assignment operation is invalid. Specifically:

 (since C++17)

Parameters

other - pair of values to replace the contents of this pair

Return value

*this.

Exceptions

1-2) (none)
3)
noexcept specification:
noexcept( is_nothrow_move_assignable<T1>::value && is_nothrow_move_assignable<T2>::value )
4) (none)

Example

See also

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