std::ranges::views::zip_transform, std::ranges::zip_transform_view

 

C++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Diagnostics library

Memory management library

Metaprogramming library (C++11)

General utilities library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Strings library

Text processing library

Numerics library

Date and time library

Input/output library

Filesystem library (C++17)

Concurrency support library (C++11)

Execution control library (C++26)

Technical specifications

Symbols index

External libraries

 

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)

Views
view_interface	subrange

Range factories
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 as_input_viewviews::as_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

 

std::ranges::zip_transform_view

Member functions

zip_transform_view::zip_transform_view

zip_transform_view::begin

zip_transform_view::end

zip_transform_view::size

Deduction guides

Iterator

Member functions

zip_transform_view::iterator::iterator

zip_transform_view::iterator::operator*

zip_transform_view::iterator::operator[]

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-=

Non-member functions

operator==(zip_transform_view::iterator) operator<=>(zip_transform_view::iterator)

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

Sentinel

Member functions

zip_transform_view::sentinel::sentinel

Non-member functions

operator==(zip_transform_view::sentinel)

operator-(zip_transform_view::sentinel)

 

Defined in header <ranges>
template< std::move_constructible F, ranges::input_range... Views > requires (ranges::view<Views> && ...) && (sizeof...(Views) > 0) && std::is_object_v<F> && std::regular_invocable< F&, ranges::range_reference_t<Views>...> && /*can-reference*/<std::invoke_result_t< F&, ranges::range_reference_t<Views>...>> class zip_transform_view : public ranges::view_interface<zip_transform_view<F, Views...>>	(1)	(since C++23)
namespace views { inline constexpr /*unspecified*/ zip_transform = /*unspecified*/; }	(2)	(since C++23)
Call signature
template< class F, ranges::viewable_range... Rs > requires /* see below */ constexpr auto zip_transform( F&& f, Rs&&... rs );		(since C++23)

1) zip_transform_view is a range adaptor that takes an invocable object and one or more views, and produces a view whose i^th element is the result of applying the invocable object to the i^th elements of all views.

A type T models the exposition-only concept /*can-reference*/ if and only if T& is a valid type.

2) views::zip_transform is a customization point object.

When calling with one argument f, let FD be std::decay_t<decltype(f)>, if:

• FD models copy_constructible,
• FD& models regular_invocable, and
• std::invoke_result_t<FD&> is an object type,

then views::zip_transform(f) is expression-equivalent to ((void)f, auto(views::empty<std::decay_t<std::invoke_result_t<FD&>>>)). Otherwise, the call to views::zip_transform is ill-formed.

When calling with more than one arguments f and rs..., views::zip_transform(f, rs...) is expression-equivalent to ranges::zip_transform_view(f, rs...).

zip_transform_view models the concepts random_access_range, bidirectional_range, forward_range, input_range, common_range, and sized_range when the underlying ranges::zip_view<Views...> models respective concepts.

Customization point objects

The name views::zip_transform denotes a customization point object, which is a const function object of a literal semiregular class type. See CustomizationPointObject for details.

Member functions

(constructor)	constructs a zip_transform_view (public member function)
begin	returns an iterator to the beginning (public member function)
end	returns an iterator or a sentinel to the end (public member function)
size	returns the number of elements, provided only if each underlying (adapted) range satisfies sized_range (public member function)
Inherited from ranges::view_interface
empty	returns whether the derived view is empty, provided only if it satisfies sized_range or forward_range (public member function of std::ranges::view_interface<D>)
cbegin (C++23)	returns a constant iterator to the beginning of the range (public member function of std::ranges::view_interface<D>)
cend (C++23)	returns a sentinel for the constant iterator of the range (public member function of std::ranges::view_interface<D>)
operator bool	returns whether the derived view is not empty, provided only if ranges::empty is applicable to it (public member function of std::ranges::view_interface<D>)
front	returns the first element in the derived view, provided if it satisfies forward_range (public member function of std::ranges::view_interface<D>)
back	returns the last element in the derived view, provided only if it satisfies bidirectional_range and common_range (public member function of std::ranges::view_interface<D>)
operator[]	returns the nth element in the derived view, provided only if it satisfies random_access_range (public member function of std::ranges::view_interface<D>)

Deduction guides

Member types

Member type	Definition
InnerView (private)	ranges::zip_view<Views...>. (exposition-only member type*)
ziperator (private)	ranges::iterator_t<const InnerView> if Const is true, otherwise ranges::iterator_t<InnerView>. (exposition-only member type*)
zentinel (private)	ranges::sentinel_t<const InnerView> if Const is true, otherwise ranges::sentinel_t<InnerView>. (exposition-only member type*)

Data members

Member object	Definition
zip_ (private)	An underlying view object of type InnerView (exposition-only member object*)
fun_ (private)	A wrapped invocable object of type movable-box<F> (exposition-only member object*)

Nested classes

iterator	the iterator type (exposition-only member class template*)
sentinel	the sentinel type used when the underlying zip_view is not a common_range (exposition-only member class template*)

Notes

Feature-test macro	Value	Std	Feature
__cpp_lib_ranges_zip	202110L	(C++23)	ranges::zip_view, std::ranges::zip_transform_view, ranges::adjacent_view, ranges::adjacent_transform_view

Example

Run this code

#include <array>
#include <iostream>
#include <list>
#include <ranges>
#include <vector>

void print(auto const rem, auto const& r)
{
    std::cout << rem << '{'; 
    for (char o[]{0,' ',0}; auto const& e : r)
        std::cout << o << e, *o = ',';
    std::cout << "}\n";
}

int main()
{
    auto v1 = std::vector<float>{1, 2, 3};
    auto v2 = std::list<short>{1, 2, 3, 4};
    auto v3 = std::to_array({1, 2, 3, 4, 5});

    auto add = [](auto a, auto b, auto c) { return a + b + c; };

    auto sum = std::views::zip_transform(add, v1, v2, v3);

    print("v1:  ", v1);
    print("v2:  ", v2);
    print("v3:  ", v3);
    print("sum: ", sum);
}

Output:

v1:  {1, 2, 3}
v2:  {1, 2, 3, 4}
v3:  {1, 2, 3, 4, 5}
sum: {3, 6, 9}

See also

ranges::zip_viewviews::zip (C++23)	a view consisting of tuples of references to corresponding elements of the adapted views (class template) (customization point object)
ranges::transform_viewviews::transform (C++20)	a view of a sequence that applies a transformation function to each element (class template) (range adaptor object)
ranges::elements_viewviews::elements (C++20)	takes a view consisting of tuple-like values and a number N and produces a view of Nth element of each tuple (class template) (range adaptor object)