Difference between revisions of "cpp/ranges/drop view"
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In all cases, {{tt|decltype((F))}} must model {{tt|std::convertible_to<D>}}. | In all cases, {{tt|decltype((F))}} must model {{tt|std::convertible_to<D>}}. | ||
| − | {{c|drop_view}} models the concepts {{lconcept|contiguous_range}}, {{lconcept|random_access_range}}, {{lconcept|bidirectional_range}}, {{lconcept|forward_range}}, {{lconcept|input_range}}, {{lconcept|common_range | + | {{c|drop_view}} models the concepts {{lconcept|contiguous_range}}, {{lconcept|random_access_range}}, {{lconcept|bidirectional_range}}, {{lconcept|forward_range}}, {{lconcept|input_range}}, and {{lconcept|common_range}} when the underlying view {{c|V}} models respective concepts. |
{{cpp/expr-eq}} | {{cpp/expr-eq}} | ||
Revision as of 18:53, 2 June 2020
| template< ranges::view V > class drop_view : public ranges::view_interface<drop_view<V>> |
(1) | (since C++20) |
| namespace views { inline constexpr /*unspecified*/ drop = /*unspecified*/; |
(2) | (since C++20) |
1) A range adaptor consisting of elements of the underlying sequence, skipping the first N elements.
2) The expression views::drop(E,F) is expression-equivalent to (where
T is std::remove_cvref_t<decltype((E))> and D is ranges::range_difference_t<decltype((E))>):
- ((void)F, static_cast<T>(E)), if
Tis a ranges::empty_view; - T{ranges::begin(E) + std::min<D>(ranges::size(E), F)}, ranges::end(E), if
Tmodels bothrandom_access_rangeandsized_range, andTis a specialization of
- std::span where
T::extent == std::dynamic_extent, - std::basic_string_view,
- ranges::iota_view, or
- ranges::subrange;
- std::span where
- otherwise, drop_view{E, F}.
decltype((F)) must model std::convertible_to<D>.drop_view models the concepts contiguous_range, random_access_range, bidirectional_range, forward_range, input_range, and common_range when the underlying view V models respective concepts.
Contents |
Expression-equivalent
Expression e is expression-equivalent to expression f, if
- e and f have the same effects, and
- either both are constant subexpressions or else neither is a constant subexpression, and
- either both are potentially-throwing or else neither is potentially-throwing (i.e. noexcept(e) == noexcept(f)).
Member functions
constructs a drop_view (public member function) | |
| returns a copy of the underlying (adapted) view (public member function) | |
| returns an iterator to the beginning (public member function) | |
| returns an iterator or a sentinel to the end (public member function) | |
returns the number of elements. Provided only if the underlying (adapted) range satisfies sized_range. (public member function) |
Deduction guides
Example
| This section is incomplete Reason: no example |
