std::ranges::split_view<V,Pattern>:: split_view

From cppreference.com
C++
Ranges library
Range adaptors
std::ranges::split_view
Defined in header <ranges>
split_view ( )

requires std:: default_initializable < V > &&

std:: default_initializable < Pattern > = default ;
(1) (since C++20)
constexpr explicit split_view ( V base, Pattern pattern ) ;
(2) (since C++20)
(3) (since C++20)

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
( P2711R1 ) 		C++20 the multi-parameter constructor was not explicit made explicit

See also

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