NAME¶

std::ranges::split_view::split_view - std::ranges::split_view::split_view

Synopsis¶

Defined in header <ranges>
split_view()

requires std::default_initializable<V> && (1) (since C++20)

std::default_initializable<Pattern> = default;
constexpr explicit split_view( V base, Pattern pattern ); (2) (since C++20)
template< ranges::forward_range R >

requires std::constructible_from<V, views::all_t<R>> &&
std::constructible_from<Pattern, ranges::single_view<
(3) (since C++20)
ranges::range_value_t<R>>>

constexpr explicit split_view( R&& r, ranges::range_value_t<R> e
);

Constructs a split_view.

Let base_ be the underlying view and pattern_ be the delimiter.

1) Default constructor. Value-initializes base_ and pattern_ with their default
member initializers respectively.
2) Initializes base_ with std::move(base) and pattern_ with std::move(pattern).
3) Initializes base_ with views::all(std::forward<R>(r)) and pattern_ with
ranges::single_view{std::move(e)}.

Parameters¶

base - the view (to be split)
pattern - view to be used as the delimiter
e - element to be used as the delimiter

Example¶

// Run this code

#include <algorithm>
#include <array>
#include <cctype>
#include <iostream>
#include <iterator>
#include <ranges>
#include <string_view>
#include <vector>

int main()
{
{
auto view = std::views::iota(1, 20)
| std::views::transform([](int x) { return x % 5; });
auto splitts = std::views::split(view, 0); // (2)
for (const auto& split : splitts)
{
std::cout << "{ ";
std::ranges::copy(split, std::ostream_iterator<int>(std::cout, " "));
std::cout << "} ";
}
}
std::cout << '\n';

{
const std::vector nums{1, -1, -1, 2, 3, -1, -1, 4, 5, 6};
const std::array delim{-1, -1};
auto splitter = std::views::split(nums, delim); // (3)
for (const auto& split : splitter)
{
std::cout << "{ ";
std::ranges::copy(split, std::ostream_iterator<int>(std::cout, " "));
std::cout << "} ";
}
}
std::cout << '\n';

{
constexpr std::string_view JupiterMoons
{
"Callisto, Europa, Ganymede, Io, and 91 more"
};
constexpr std::string_view delim{", "};
std::ranges::split_view moons_extractor{JupiterMoons, delim}; // (3)
auto is_moon = std::views::filter([](auto str)
{
return std::isupper(str[0]);
});
std::cout << "Some moons of Jupiter: ";
for (const auto moon : moons_extractor | is_moon)
std::cout << std::string_view(moon) << ' ';
}
std::cout << '\n';
}

Output:¶

{ 1 2 3 4 } { 1 2 3 4 } { 1 2 3 4 } { 1 2 3 4 }
{ 1 } { 2 3 } { 4 5 6 }
Some moons of Jupiter: Callisto Europa Ganymede Io

Defect reports

The following behavior-changing defect reports were applied retroactively to
previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 3714 C++20 the multi-parameter constructor was not made explicit
(P2711R1) explicit

See also¶

constructor constructs a lazy_split_view
(C++20) (public member function of std::ranges::lazy_split_view<V,Pattern>)