14#ifndef RANGES_V3_ALGORITHM_FOR_EACH_N_HPP
15#define RANGES_V3_ALGORITHM_FOR_EACH_N_HPP
21#include <range/v3/algorithm/result_types.hpp>
29#include <range/v3/utility/static_const.hpp>
31#include <range/v3/detail/prologue.hpp>
37 RANGES_FUNC_BEGIN(for_each_n)
40 template(typename I, typename F, typename P =
identity)(
43 constexpr I RANGES_FUNC(for_each_n)(I first, iter_difference_t<I> n, F fun, P proj = P{})
45 RANGES_EXPECT(0 <= n);
47 auto b = uncounted(first);
48 for(; 0 < n; ++b, --n)
49 invoke(fun, invoke(proj, *b));
50 return recounted(first, b, norig);
54 template(
typename Rng,
typename F,
typename P = identity)(
55 requires input_range<Rng> AND
56 indirectly_unary_invocable<F, projected<iterator_t<Rng>, P>>)
57 constexpr borrowed_iterator_t<Rng> RANGES_FUNC(for_each_n)(
58 Rng && rng, range_difference_t<Rng> n, F fun, P proj = P{})
61 RANGES_EXPECT(n <= distance(rng));
63 return (*
this)(begin(rng), n, detail::move(fun), detail::move(proj));
66 RANGES_FUNC_END(for_each_n)
70 using ranges::for_each_n;
75#include <range/v3/detail/epilogue.hpp>
The indirectly_unary_invocable concept.
Definition identity.hpp:25