W3cubDocs

/C++

operator==,!=,<,<=,>,>=,<=>(std::stack)

template< class T, class Container >
bool operator==( const std::stack<T, Container>& lhs,
                 const std::stack<T, Container>& rhs );
(1)
template< class T, class Container >
bool operator!=( const std::stack<T, Container>& lhs,
                 const std::stack<T, Container>& rhs );
(2)
template< class T, class Container >
bool operator< ( const std::stack<T, Container>& lhs,
                 const std::stack<T, Container>& rhs );
(3)
template< class T, class Container >
bool operator<=( const std::stack<T, Container>& lhs,
                 const std::stack<T, Container>& rhs );
(4)
template< class T, class Container >
bool operator> ( const std::stack<T, Container>& lhs,
                 const std::stack<T, Container>& rhs );
(5)
template< class T, class Container >
bool operator>=( const std::stack<T, Container>& lhs,
                 const std::stack<T, Container>& rhs );
(6)
template< class T, std::three_way_comparable Container >
std::compare_three_way_result_t<Container>
    operator<=>( const std::stack<T, Container>& lhs,
                 const std::stack<T, Container>& rhs );
(7) (since C++20)

Compares the contents of the underlying containers of two container adaptors. The comparison is done by applying the corresponding operator to the underlying containers.

Parameters

lhs, rhs - container adaptors whose contents to compare
-T must meet the requirements of EqualityComparable.

Return value

1-6) true if the corresponding comparison yields true, false otherwise.
7) Result of three-way comparison on underlying containers.

Complexity

Linear in the size of the container.

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 410 C++98 the semantics of all comparison operators were missing added

© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
https://en.cppreference.com/w/cpp/container/stack/operator_cmp