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operator==,<,>,<=,>=,<=>(ranges::transform_view::iterator)

friend constexpr bool operator==( const /*iterator*/& x, const /*iterator*/& y )
  requires std::equality_comparable<ranges::iterator_t<Base>>;
 (1) (since C++20) 
friend constexpr bool operator<( const /*iterator*/& x, const /*iterator*/& y )
  requires ranges::random_access_range<Base>;
 (2) (since C++20) 
friend constexpr bool operator>( const /*iterator*/& x, const /*iterator*/& y )
  requires ranges::random_access_range<Base>;
 (3) (since C++20) 
friend constexpr bool operator<=( const /*iterator*/& x, const /*iterator*/& y )
  requires ranges::random_access_range<Base>;
 (4) (since C++20) 
friend constexpr bool operator>=( const /*iterator*/& x, const /*iterator*/& y )
  requires ranges::random_access_range<Base>;
 (5) (since C++20) 
friend constexpr auto operator<=>( const /*iterator*/& x, const /*iterator*/& y )
  requires ranges::random_access_range<Base> &&
           std::three_way_comparable<ranges::iterator_t<Base>>;
 (6) (since C++20)

Compares the underlying iterators.

1) Equivalent to return x.current_ == y.current_;, where current_ is the underlying iterator.
2) Equivalent to return x.current_ < y.current_;, where current_ is the underlying iterator.
3) Equivalent to return y < x;
4) Equivalent to return !(y < x);
5) Equivalent to return !(x < y);
6) Equivalent to return x.current_ <=> y.current_;, where current_ is the underlying iterator.

These functions are not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::ranges::transform_view::iterator<Const> is an associated class of the arguments.

The != operator is synthesized from operator==.

Parameters

x, y - iterators to compare

Return value

result of comparison.

See also

(C++20)
 compares a sentinel with an iterator returned from transform_view::begin
(function)

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https://en.cppreference.com/w/cpp/ranges/transform_view/iterator/operator_cmp