[string.view.comparison]

Let S be basic_string_view<charT, traits>, and sv be an instance of S.

Implementations shall provide sufficient additional overloads marked constexpr and noexcept so that an object t with an implicit conversion to S can be compared according to Table 71 .

Table 71: Additional basic_string_view comparison overloads [tab:string.view.comparison.overloads]

Expression	Equivalent to
t == sv	S(t) == sv
sv == t	sv == S(t)
t != sv	S(t) != sv
sv != t	sv != S(t)
t < sv	S(t) < sv
sv < t	sv < S(t)
t > sv	S(t) > sv
sv > t	sv > S(t)
t <= sv	S(t) <= sv
sv <= t	sv <= S(t)
t >= sv	S(t) >= sv
sv >= t	sv >= S(t)
t <=> sv	S(t) <=> sv
sv <=> t	sv <=> S(t)

[Example

A sample conforming implementation for operator== would be:

template<class charT, class traits>
  constexpr bool operator==(basic_string_view<charT, traits> lhs,
                            basic_string_view<charT, traits> rhs) noexcept {
    return lhs.compare(rhs) == 0;
  }
template<class charT, class traits>
  constexpr bool operator==(basic_string_view<charT, traits> lhs,
                            type_identity_t<basic_string_view<charT, traits>> rhs) noexcept {
    return lhs.compare(rhs) == 0;
  }

— end example

]

🔗

template<class charT, class traits>
  constexpr bool operator==(basic_string_view<charT, traits> lhs,
                            basic_string_view<charT, traits> rhs) noexcept;

Returns: lhs.compare(rhs) == 0.

🔗

template<class charT, class traits>
  constexpr see below operator<=>(basic_string_view<charT, traits> lhs,
                                  basic_string_view<charT, traits> rhs) noexcept;

21 Strings library [strings]

21.4 String view classes [string.view]

21.4.4 Non-member comparison functions [string.view.comparison]