std::ranges::cartesian_product_view<First, Vs...>::begin

 

C++

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Feature test macros (C++20)

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Concepts library (C++20)

Metaprogramming library (C++11)

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Ranges library (C++20)

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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::cartesian_product_view

Member functions

cartesian_product_view::cartesian_product_view (C++23)

cartesian_product_view::begin (C++23)

cartesian_product_view::end (C++23)

cartesian_product_view::size (C++23)

Deduction guides

Iterator

Member functions

cartesian_product_view::iterator::iterator (C++23)

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

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

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

cartesian_product_view::iterator::next (C++23)

cartesian_product_view::iterator::prev (C++23)

cartesian_product_view::iterator::distance_from (C++23)

Non-member functions

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

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

iter_move(cartesian_product_view::iterator) (C++23)

iter_swap(cartesian_product_view::iterator) (C++23)

 

constexpr iterator<false> begin()     requires (!__simple_view<First> || ... || !__simple_view<Vs>);	(1)	(since C++23)
constexpr iterator<true> begin() const     requires (ranges::range<const First> && ... && ranges::range<const Vs>);	(2)	(since C++23)

Returns an iterator to the first element of the cartesian_product_view.

Let bases_ be the tuple of underlying views.

1) Equivalent to return /*iterator*/<false>(__tuple_transform(ranges::begin, bases_));.

2) Equivalent to return /*iterator*/<true>(__tuple_transform(ranges::begin, bases_));.

Parameters

(none)

Return value

Iterator to the first element.

Example

Can be checked online with Compiler Explorer.

Run this code

#include <array>
#include <print>
#include <ranges>
#include <string_view>
#include <tuple>
using namespace std::literals;
 
int main()
{
    constexpr auto a = std::array{ "Curiously"sv, "Recurring"sv, "Template"sv, "Pattern"sv };
 
    constexpr auto v = std::ranges::cartesian_product_view(a[0], a[1], a[2], a[3]);
 
    constexpr std::tuple<char const&,
                         char const&,
                         char const&,
                         char const&> first { *v.begin() };
 
    std::println("{}{}{}{}",
                 std::get<0>(first),
                 std::get<1>(first),
                 std::get<2>(first),
                 std::get<3>(first));
}

Output:

CRTP

See also

end (C++23)	returns an iterator or a sentinel to the end (public member function)
ranges::begin (C++20)	returns an iterator to the beginning of a range (customization point object)