std::ranges::zip_transform_view<F,Views...>::size

 

C++

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Standard library

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Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Metaprogramming library (C++11)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

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Filesystem library (C++17)

Regular expressions library (C++11)

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Technical specifications

Symbols index

External libraries

 

Ranges library

Range access
begin cbegin end cend	rbegin crbegin rend crend	size ssize data cdata	empty
Range conversions
to (C++23)
Range primitives
range_size_trange_difference_trange_value_trange_reference_t	iterator_tconst_iterator_tsentinel_tconst_sentinel_t (C++23)(C++23)	range_const_reference_trange_rvalue_reference_trange_common_reference_t (C++23)	elements_of (C++23)
Dangling iterator handling
dangling	borrowed_iterator_t	borrowed_subrange_t
Range concepts
range borrowed_range sized_range constant_range (C++23)	common_range view viewable_range	input_range output_range forward_range	bidirectional_range random_access_range contiguous_range
Views
view_interface	subrange
Range factories
empty_viewviews::empty single_viewviews::single	iota_viewviews::iota repeat_viewviews::repeat (C++23)(C++23)	basic_istream_viewviews::istream
Range adaptors
views::all_tviews::all ref_view owning_view as_rvalue_viewviews::as_rvalue (C++23)(C++23) filter_viewviews::filter transform_viewviews::transform take_viewviews::take take_while_viewviews::take_while	drop_viewviews::drop drop_while_viewviews::drop_while join_viewviews::join join_with_viewviews::join_with (C++23)(C++23) lazy_split_viewviews::lazy_split split_viewviews::split views::counted common_viewviews::common	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 objects
Range adaptor closure objects
range_adaptor_closure (C++23)
Helper items
copyable-box movable-box (until C++23)(C++23)	simple-view non-propagating-cache

 

std::ranges::zip_transform_view

Member functions

zip_transform_view::zip_transform_view (C++23)

zip_transform_view::begin (C++23)

zip_transform_view::end (C++23)

zip_transform_view::size (C++23)

Deduction guides

Iterator

Member functions

zip_transform_view::iterator::iterator (C++23)

zip_transform_view::iterator::operator* (C++23)

zip_transform_view::iterator::operator[] (C++23)

zip_transform_view::iterator::operator++ zip_transform_view::iterator::operator++(int) zip_transform_view::iterator::operator-- zip_transform_view::iterator::operator--(int) zip_transform_view::iterator::operator+= zip_transform_view::iterator::operator-= (C++23)(C++23)(C++23)(C++23)(C++23)(C++23)

Non-member functions

operator==(zip_transform_view::iterator) operator<=>(zip_transform_view::iterator) (C++23)(C++23)

operator+(zip_transform_view::iterator) operator-(zip_transform_view::iterator) (C++23)(C++23)

Sentinel

Member functions

zip_transform_view::sentinel::sentinel (C++23)

Non-member functions

operator==(zip_transform_view::sentinel) (C++23)

operator-(zip_transform_view::sentinel) (C++23)

 

constexpr auto size()     requires ranges::sized_range</*InnerView*/>;	(1)	(since C++23)
constexpr auto size() const     requires ranges::sized_range<const /*InnerView*/>	(2)	(since C++23)

Returns the number of elements in the zip_transform_view. Provided only if each underlying (adapted) range satisfies sized_range.

1,2) Equivalent to: return zip_.size();.

Parameters

(none)

Return value

The number of elements, which is the minimum size among all sizes of adapted views.

Example

Run this code

#include <algorithm>
#include <cassert>
#include <deque>
#include <forward_list>
#include <functional>
#include <iostream>
#include <ranges>
#include <vector>
 
int main()
{
    auto x = std::vector{1, 2, 3, 4, 5};
    auto y = std::deque<short>{10, 20, 30};
    auto z = std::forward_list{100., 200.};
 
    auto v1 = std::views::zip_transform(std::plus, x, y);
    assert(v1.size() == std::min(x.size(), y.size()));
    assert(v1.size() == 3);
    for (int i : v1) std::cout << i << '\n';
 
    [[maybe_unused]] auto v2 = std::views::zip_transform(std::plus, x, z);
//  auto sz = v2.size(); // Error, v2 does not have size():
    static_assert(not std::ranges::sized_range<decltype(z)>);
}

Output:

11 22 33

See also

ranges::size (C++20)	returns an integer equal to the size of a range (customization point object)
ranges::ssize (C++20)	returns a signed integer equal to the size of a range (customization point object)