std::ranges::chunk_view<V>::reserve_hint

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Ranges library

Range access

begin
cbegin
end
cend

rbegin
crbegin
rend
crend

size
ssize
data
cdata

reserve_hint (C++26)
empty

Range conversions
std::from_range_t std::from_range (C++23)(C++23)
to (C++23)

Dangling iterator handling
dangling
borrowed_iterator_t
borrowed_subrange_t

Range primitives

range_size_trange_difference_trange_value_t
elements_of (C++23)

iterator_tconst_iterator_tsentinel_tconst_sentinel_t

(C++23)(C++23)

range_reference_trange_const_reference_trange_rvalue_reference_trange_common_reference_t

(C++23)

Range concepts

range
borrowed_range
common_range

sized_range
viewable_range
view

input_range
output_range
forward_range

bidirectional_range
random_access_range
contiguous_range

approximately_sized_range (C++26)
constant_range (C++23)

empty_viewviews::empty

single_viewviews::single

basic_istream_viewviews::istream

iota_viewviews::iota

repeat_viewviews::repeat

(C++23)(C++23)

Range adaptors

views::all_tviews::all
as_rvalue_viewviews::as_rvalue (C++23)(C++23)
filter_viewviews::filter
transform_viewviews::transform
take_viewviews::take
take_while_viewviews::take_while
common_viewviews::common
views::counted
to_input_viewviews::to_input (C++26)(C++26)

ref_view
drop_viewviews::drop
drop_while_viewviews::drop_while
lazy_split_viewviews::lazy_split
split_viewviews::split
join_viewviews::join
join_with_viewviews::join_with (C++23)(C++23)
concat_viewviews::concat (C++26)(C++26)
cache_latest_viewviews::cache_latest (C++26)(C++26)

owning_view
reverse_viewviews::reverse
as_const_viewviews::as_const (C++23)(C++23)
elements_viewviews::elements
keys_viewviews::keys
values_viewviews::values
enumerate_viewviews::enumerate (C++23)(C++23)
zip_viewviews::zip (C++23)(C++23)
zip_transform_viewviews::zip_transform (C++23)(C++23)

adjacent_viewviews::adjacent (C++23)(C++23)
views::pairwise (C++23)
adjacent_transform_viewviews::adjacent_transform (C++23)(C++23)
views::pairwise_transform (C++23)
chunk_viewviews::chunk (C++23)(C++23)
slide_viewviews::slide (C++23)(C++23)
chunk_by_viewviews::chunk_by (C++23)(C++23)
stride_viewviews::stride (C++23)(C++23)
cartesian_product_viewviews::cartesian_product (C++23)(C++23)

Range generators
std::generator (C++23)

Range adaptor closure objects
range_adaptor_closure (C++23)

Range adaptor objects

Helper items

copyable-box
movable-box

(until C++23) (C++23)

simple-view
non-propagating-cache

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std::ranges::chunk_view

Member functions

chunk_view::chunk_view

chunk_view::reserve_hint

(C++26)

Classes for`input_range`s
Deduction guides
outer-iterator
chunk_view::outer-iterator::outer-iterator
chunk_view::outer-iterator::operator=
chunk_view::outer-iterator::operator*
chunk_view::outer-iterator::operator++ chunk_view::outer-iterator::operator++(int)
operator==(chunk_view::outer-iterator)
operator-(chunk_view::outer-iterator)
outer-iterator::value_type
chunk_view::outer-iterator::value_type::value_type
chunk_view::outer-iterator::value_type::begin
chunk_view::outer-iterator::value_type::end
chunk_view::outer-iterator::value_type::size
inner-iterator
chunk_view::inner-iterator::inner-iterator
chunk_view::inner-iterator::operator=
chunk_view::inner-iterator::base
chunk_view::inner-iterator::operator*
chunk_view::inner-iterator::operator++ chunk_view::inner-iterator::operator++(int)
operator==(chunk_view::inner-iterator)
operator-(chunk_view::inner-iterator)
iter_move(chunk_view::inner-iterator)
iter_swap(chunk_view::inner-iterator)

Class template for `forward_range`s
iterator
chunk_view::iterator::iterator
chunk_view::iterator::base
chunk_view::iterator::operator*
chunk_view::iterator::operator[]
chunk_view::iterator::operator++ chunk_view::iterator::operator++(int) chunk_view::iterator::operator-- chunk_view::iterator::operator--(int) chunk_view::iterator::operator+= chunk_view::iterator::operator-=
operator==(chunk_view::iterator) operator<(chunk_view::iterator) operator>(chunk_view::iterator) operator<=(chunk_view::iterator) operator>=(chunk_view::iterator) operator<=>(chunk_view::iterator)
operator+(chunk_view::iterator) operator-(chunk_view::iterator)

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constexprauto reserve_hint() requires ranges::approximately_sized_range<V>	(1)	(since C++26)
constexprauto reserve_hint()const requires ranges::approximately_sized_range<const V>	(2)	(since C++26)

Equivalent to

using DT=ranges::range_difference_t<decltype((base_))>;
auto s=static_cast<DT>(ranges::reserve_hint(base_));
return to-unsigned-like(div-ceil(s, n_));