ranges::iota_view, views::iota

a view consisting of a sequence generated by repeatedly incrementing an initial value More...

Detailed Description

A range factory that generates a sequence of elements by repeatedly incrementing an initial value. Can be either bounded or unbounded (infinite).

Example

#include <algorithm>
#include <iostream>
#include <ranges>
 
struct Bound {
  int bound;
  // Since C++20
  bool operator==(int x) const { return x == bound; }
 
  // Until C++20
  bool operator!=(int x) const { return x != bound; }
  friend constexpr bool operator==(int x, Bound b) { return x == b.bound;}
  friend constexpr bool operator!=(int x, Bound b) { return x != b.bound;}
};
 
int main()
{
    for (int i : std::ranges::iota_view<int, int>{1, 10})
        std::cout << i << ' ';
    std::cout << '\n';
 
    for (int i : std::views::iota(1, 10))
        std::cout << i << ' ';
    std::cout << '\n';
 
    // C++17
    for (int i : std::views::iota(1, Bound{10}))
        std::cout << i << ' ';
    std::cout << '\n';
 
    // C++20
    for (int i : std::views::iota(1) | std::views::take(9))
        std::cout << i << ' ';
    std::cout << '\n';
 
    // Not implemented yet
    std::ranges::for_each(std::views::iota(1, 10), [](int i)
    {
        std::cout << i << ' ';
    });
    std::cout << '\n';
}

See also

std::ranges::iota_view

Classes
class	iota_view< W, Bound >
struct	enable_borrowed_range< iota_view< W, Bound > >

Variables
constexpr VCCC_INLINE_OR_STATIC detail::iota_niebloid	iota {}

Variable Documentation

iota

constexpr VCCC_INLINE_OR_STATIC detail::iota_niebloid iota {}

constexpr

views::iota(e) and views::iota(e, f) are expression-equivalent to iota_view(e) and iota_view(e, f) respectively for any suitable subexpressions e and f