# std::ranges::view::empty, std::ranges::empty_view

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< cpp‎ | ranges

template<class T> requires is_object_v<T> class empty_view : public view_interface<empty_view<T>> | (1) | (since C++20)
namespace view { template<class T> inline constexpr empty_view<T> empty{}; } | (2) | (since C++20)

1) A range adaptor that produces a `View` of no elements of a particular type.
2) Variable template for `empty_view`.

### Member functions

## std::ranges::empty_view::begin

static constexpr T* begin() noexcept { return nullptr; } |  |

`empty_view` does not reference any element.

## std::ranges::empty_view::end

static constexpr T* end() noexcept { return nullptr; } |  |

`empty_view` does not reference any element.

## std::ranges::empty_view::data

static constexpr T* data() noexcept { return nullptr; } |  |

`empty_view` does not reference any element.

## std::ranges::empty_view::size

static constexpr std::ptrdiff_t size() noexcept { return 0; } |  |

`empty_view` is always empty.

## std::ranges::empty_view::empty

static constexpr bool empty() noexcept { return true; } |  |

`empty_view` is always empty.

### Non-member functions

## begin, end(std::ranges::empty_view)

friend constexpr T* begin(empty_view) noexcept { return nullptr; } | (1) |
friend constexpr T* end(empty_view) noexcept { return nullptr; } | (2) |

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

### Example

Run this code

    #include <ranges>

    int main()
    {
        std::ranges::empty_view<int> e;
        static_assert(std::ranges::empty(e));
        static_assert(0 == e.size());
    }

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