std::ranges:: contiguous_range

From cppreference.com
C++
Ranges library
Range adaptors
Defined in header <ranges>
template < class T >

concept contiguous_range =
ranges:: random_access_range < T > &&
std:: contiguous_iterator < ranges:: iterator_t < T >> &&
requires ( T & t ) {
{ ranges:: data ( t ) } - >
std:: same_as < std:: add_pointer_t < ranges:: range_reference_t < T >>> ;

} ;
(since C++20)

The contiguous_range concept is a refinement of range for which ranges::begin returns a model of contiguous_iterator and the customization point ranges::data is usable.

Semantic requirements

T models contiguous_range only if given an expression e such that decltype ( ( e ) ) is T & , std:: to_address ( ranges:: begin ( e ) ) == ranges:: data ( e ) .

Example

Run this code 
#include <array>
#include <deque>
#include <list>
#include <mdspan>
#include <ranges>
#include <set>
#include <span>
#include <string_view>
#include <valarray>
#include <vector>
 
template<typename T>
concept CR = std::ranges::contiguous_range<T>;
 
// zstring being a ranges::contiguous_range doesn't have to be a ranges::sized_range
struct zstring
{
    struct sentinel
    {
        friend constexpr bool operator==(const char* str, sentinel) noexcept
        { return *str == '\0'; }
    };
 
    const char* str;
 
    const char* begin() const noexcept { return str; }
    sentinel end() const noexcept { return {}; }
};
 
int main()
{
    int a[4];
    static_assert(
            CR<std::vector<int>> and
        not CR<std::vector<bool>> and
        not CR<std::deque<int>> and
            CR<std::valarray<int>> and
            CR<decltype(a)> and
        not CR<std::list<int>> and
        not CR<std::set<int>> and
            CR<std::array<std::list<int>,42>> and
            CR<std::string_view> and
            CR<zstring> and
            CR<std::span<const int>> and
        not CR<std::mdspan<int, std::dims<1>>>
    );
}

See also

(C++20)
specifies that a range knows its size in constant time
(concept)
(C++20)
specifies a range whose iterator type satisfies random_access_iterator
(concept)
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