1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
|
// Range v3 library
//
// Copyright Eric Niebler 2014-present
// Copyright Rostislav Khlebnikov 2017
//
// Use, modification and distribution is subject to the
// Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//
// Project home: https://github.com/ericniebler/range-v3
#include <vector>
#include <range/v3/core.hpp>
#include <range/v3/algorithm/for_each_n.hpp>
#include "../array.hpp"
#include "../simple_test.hpp"
struct S
{
void p() const { *p_ += i_; }
int *p_;
int i_;
};
constexpr bool test_constexpr()
{
// lambda closure types are non-literal types before C++17
struct
{
constexpr void operator()(int i)
{
sum_ += i;
}
int sum_ = 0;
} fun;
constexpr test::array<int, 5> v1{{1, 2, 4, 6}};
STATIC_CHECK_RETURN(ranges::for_each_n(v1.begin(), 2, ranges::ref(fun)) ==
v1.begin() + 2);
STATIC_CHECK_RETURN(ranges::for_each_n(v1, 2, ranges::ref(fun)) == v1.begin() + 2);
STATIC_CHECK_RETURN(fun.sum_ == 3 * 2);
return true;
}
int main()
{
int sum = 0;
auto const fun = [&](int i){ sum += i; };
std::vector<int> v1 { 1, 2, 4, 6 };
CHECK(ranges::for_each_n(v1.begin(), 2, fun) == v1.begin() + 2);
CHECK(ranges::for_each_n(v1, 2, fun) == v1.begin() + 2);
CHECK(sum == 3 * 2);
sum = 0;
auto const rfun = [&](int & i){ sum += i; };
auto const sz = static_cast<int>(v1.size());
CHECK(ranges::for_each_n(v1.begin(), sz, rfun) == v1.end());
CHECK(ranges::for_each_n(v1, sz, rfun) == v1.end());
CHECK(sum == 13 * 2);
sum = 0;
std::vector<S> v2{{&sum, 1}, {&sum, 2}, {&sum, 4}, {&sum, 6}};
CHECK(ranges::for_each_n(v2.begin(), 3, &S::p) == v2.begin() + 3);
CHECK(ranges::for_each_n(v2, 3, &S::p) == v2.begin() + 3);
CHECK(sum == 7 * 2);
sum = 0;
CHECK(ranges::for_each_n(v2.begin(), 4, fun, &S::i_) == v2.begin() + 4);
CHECK(ranges::for_each_n(v2, 4, fun, &S::i_) == v2.begin() + 4);
CHECK(sum == 13 * 2);
STATIC_CHECK(test_constexpr());
return ::test_result();
}
|
