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[range.all]
# 25 Ranges library [[ranges]](./#ranges)
## 25.7 Range adaptors [[range.adaptors]](range.adaptors#range.all)
### 25.7.6 All view [range.all]
#### [25.7.6.1](#general) General [[range.all.general]](range.all.general)
[1](#general-1)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L4494)
views::all returns a view that includes all elements of
its range argument[.](#general-1.sentence-1)
[2](#general-2)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L4499)
The name views::all denotes a
range adaptor object ([[range.adaptor.object]](range.adaptor.object "25.7.2Range adaptor objects"))[.](#general-2.sentence-1)
Given a subexpression E, the expressionviews::all(E) is expression-equivalent to:
- [(2.1)](#general-2.1)
*decay-copy*(E) if the decayed type of E models [view](range.view#concept:view "25.4.5Views[range.view]")[.](#general-2.1.sentence-1)
- [(2.2)](#general-2.2)
Otherwise, ref_view{E} if that expression is well-formed[.](#general-2.2.sentence-1)
- [(2.3)](#general-2.3)
Otherwise, owning_view{E}[.](#general-2.3.sentence-1)
#### [25.7.6.2](#range.ref.view) Class template ref_view [[range.ref.view]](range.ref.view)
[1](#range.ref.view-1)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L4515)
ref_view is a view of the elements of some other range[.](#range.ref.view-1.sentence-1)
[🔗](#lib:ref_view)
namespace std::ranges {template<[range](range.range#concept:range "25.4.2Ranges[range.range]") R>requires is_object_v<R>class ref_view : public view_interface<ref_view<R>> {private: R* *r_*; // *exposition only*public:template<[*different-from*](range.utility.helpers#concept:different-from "25.5.2Helper concepts[range.utility.helpers]")<ref_view> T>requires *see below*constexpr ref_view(T&& t); constexpr R& base() const { return **r_*; }constexpr iterator_t<R> begin() const { return ranges::begin(**r_*); }constexpr sentinel_t<R> end() const { return ranges::end(**r_*); }constexpr bool empty() constrequires requires { ranges::empty(**r_*); }{ return ranges::empty(**r_*); }constexpr auto size() const requires [sized_range](range.sized#concept:sized_range "25.4.4Sized ranges[range.sized]")<R>{ return ranges::size(**r_*); }constexpr auto reserve_hint() const requires [approximately_sized_range](range.approximately.sized#concept:approximately_sized_range "25.4.3Approximately sized ranges[range.approximately.sized]")<R>{ return ranges::reserve_hint(**r_*); }constexpr auto data() const requires [contiguous_range](range.refinements#concept:contiguous_range "25.4.6Other range refinements[range.refinements]")<R>{ return ranges::data(**r_*); }}; template<class R> ref_view(R&) -> ref_view<R>;}
[🔗](#lib:ref_view,constructor)
`template<[different-from](range.utility.helpers#concept:different-from "25.5.2Helper concepts[range.utility.helpers]")<ref_view> T>
requires see below
constexpr ref_view(T&& t);
`
[2](#range.ref.view-2)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L4563)
*Effects*: Initializes *r_* withaddressof(static_cast<R&>(std::forward<T>(t)))[.](#range.ref.view-2.sentence-1)
[3](#range.ref.view-3)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L4568)
*Remarks*: Let *FUN* denote the exposition-only functionsvoid *FUN*(R&);void *FUN*(R&&) = delete;
The expression in the [*requires-clause*](temp.pre#nt:requires-clause "13.1Preamble[temp.pre]") is equivalent to:[convertible_to](concept.convertible#concept:convertible_to "18.4.4Concept convertible_­to[concept.convertible]")<T, R&> && requires { *FUN*(declval<T>()); }
#### [25.7.6.3](#range.owning.view) Class template owning_view [[range.owning.view]](range.owning.view)
[1](#range.owning.view-1)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L4583)
owning_view is a move-only view
of the elements of some other range[.](#range.owning.view-1.sentence-1)
[🔗](#lib:owning_view)
namespace std::ranges {template<[range](range.range#concept:range "25.4.2Ranges[range.range]") R>requires [movable](concepts.object#concept:movable "18.6Object concepts[concepts.object]")<R> && (!*is-initializer-list*<R>) // see [[range.refinements]](range.refinements "25.4.6Other range refinements")class owning_view : public view_interface<owning_view<R>> {private: R *r_* = R(); // *exposition only*public: owning_view() requires [default_initializable](concept.default.init#concept:default_initializable "18.4.12Concept default_­initializable[concept.default.init]")<R> = default; constexpr owning_view(R&& t);
owning_view(owning_view&&) = default;
owning_view& operator=(owning_view&&) = default; constexpr R& base() & noexcept { return *r_*; }constexpr const R& base() const & noexcept { return *r_*; }constexpr R&& base() && noexcept { return std::move(*r_*); }constexpr const R&& base() const && noexcept { return std::move(*r_*); }constexpr iterator_t<R> begin() { return ranges::begin(*r_*); }constexpr sentinel_t<R> end() { return ranges::end(*r_*); }constexpr auto begin() const requires [range](range.range#concept:range "25.4.2Ranges[range.range]")<const R>{ return ranges::begin(*r_*); }constexpr auto end() const requires [range](range.range#concept:range "25.4.2Ranges[range.range]")<const R>{ return ranges::end(*r_*); }constexpr bool empty() requires requires { ranges::empty(*r_*); }{ return ranges::empty(*r_*); }constexpr bool empty() const requires requires { ranges::empty(*r_*); }{ return ranges::empty(*r_*); }constexpr auto size() requires [sized_range](range.sized#concept:sized_range "25.4.4Sized ranges[range.sized]")<R>{ return ranges::size(*r_*); }constexpr auto size() const requires [sized_range](range.sized#concept:sized_range "25.4.4Sized ranges[range.sized]")<const R>{ return ranges::size(*r_*); }constexpr auto reserve_hint() requires [approximately_sized_range](range.approximately.sized#concept:approximately_sized_range "25.4.3Approximately sized ranges[range.approximately.sized]")<R>{ return ranges::reserve_hint(*r_*); }constexpr auto reserve_hint() const requires [approximately_sized_range](range.approximately.sized#concept:approximately_sized_range "25.4.3Approximately sized ranges[range.approximately.sized]")<const R>{ return ranges::reserve_hint(*r_*); }constexpr auto data() requires [contiguous_range](range.refinements#concept:contiguous_range "25.4.6Other range refinements[range.refinements]")<R>{ return ranges::data(*r_*); }constexpr auto data() const requires [contiguous_range](range.refinements#concept:contiguous_range "25.4.6Other range refinements[range.refinements]")<const R>{ return ranges::data(*r_*); }};}
[🔗](#lib:owning_view,constructor)
`constexpr owning_view(R&& t);
`
[2](#range.owning.view-2)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L4645)
*Effects*: Initializes *r_* with std::move(t)[.](#range.owning.view-2.sentence-1)