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

Defined in header <string_view> 
template< class CharT, class Traits >
constexpr bool operator==( basic_string_view <CharT,Traits> lhs, 
                           basic_string_view <CharT,Traits> rhs ) noexcept;
 (1) (since C++17) 
template< class CharT, class Traits >
constexpr bool operator!=( basic_string_view <CharT,Traits> lhs, 
                           basic_string_view <CharT,Traits> rhs ) noexcept;
 (2) (since C++17) 
template< class CharT, class Traits >
constexpr bool operator<( basic_string_view <CharT,Traits> lhs, 
                          basic_string_view <CharT,Traits> rhs ) noexcept;
 (3) (since C++17) 
template< class CharT, class Traits >
constexpr bool operator<=( basic_string_view <CharT,Traits> lhs, 
                           basic_string_view <CharT,Traits> rhs ) noexcept;
 (4) (since C++17) 
template< class CharT, class Traits >
constexpr bool operator>( basic_string_view <CharT,Traits> lhs, 
                          basic_string_view <CharT,Traits> rhs ) noexcept;
 (5) (since C++17) 
template< class CharT, class Traits >
constexpr bool operator>=( basic_string_view <CharT,Traits> lhs, 
                           basic_string_view <CharT,Traits> rhs ) noexcept;
 (6) (since C++17)

Compares two views.

All comparisons are done via the compare() member function (which itself is defined in terms of Traits::compare()):

  • Two views are equal if both the size of lhs and rhs are equal and each character in lhs has an equivalent character in rhs at the same position.
  • The ordering comparisons are done lexicographically -- the comparison is performed by a function equivalent to std::lexicographical_compare.

The implementation shall provide sufficient additional constexpr and noexcept overloads of these functions so that a basic_string_view<CharT,Traits> object sv may be compared to another object t with an implicit conversion to basic_string_view<CharT,Traits>, with semantics identical to comparing sv and basic_string_view<CharT,Traits>(t).

Parameters

lhs, rhs - views to compare

Return value

true if the corresponding comparison holds, false otherwise.

Complexity

Linear in the size of the views.

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http://en.cppreference.com/w/cpp/string/basic_string_view/operator_cmp