File: fold.cpp

package info (click to toggle)
boost1.74 1.74.0-9
  • links: PTS, VCS
  • area: main
  • in suites: bullseye
  • size: 464,084 kB
  • sloc: cpp: 3,338,324; xml: 131,293; python: 33,088; ansic: 14,336; asm: 4,034; sh: 3,351; makefile: 1,193; perl: 1,036; yacc: 478; php: 212; ruby: 102; lisp: 24; sql: 13; csh: 6
file content (93 lines) | stat: -rw-r--r-- 3,010 bytes parent folder | download | duplicates (12)
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
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
/*=============================================================================
    Copyright (c) 2017 Paul Fultz II
    fold.cpp
    Distributed under 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)
==============================================================================*/
#include <boost/hof/fold.hpp>
#include "test.hpp"

struct max_f
{
    template<class T, class U>
    constexpr T operator()(T x, U y) const noexcept
    {
        return x > y ? x : y;
    }
};

struct sum_f
{
    template<class T, class U>
    constexpr T operator()(T x, U y) const BOOST_HOF_RETURNS_DEDUCE_NOEXCEPT(x+y)
    {
        return x + y;
    }
};

#if BOOST_HOF_HAS_NOEXCEPT_DEDUCTION
BOOST_HOF_TEST_CASE()
{
    static_assert(noexcept(boost::hof::fold(max_f(), 0)(2, 3, 4, 5)), "noexcept fold");
    static_assert(noexcept(boost::hof::fold(sum_f(), 0)(2, 3, 4, 5)), "noexcept fold");
    static_assert(!noexcept(boost::hof::fold(sum_f(), std::string())("hello", "-", "world")), "noexcept fold");
}
#endif

BOOST_HOF_TEST_CASE()
{
    BOOST_HOF_TEST_CHECK(boost::hof::fold(max_f(), 0)(2, 3, 4, 5) == 5);
    BOOST_HOF_TEST_CHECK(boost::hof::fold(max_f(), 0)(5, 4, 3, 2) == 5);
    BOOST_HOF_TEST_CHECK(boost::hof::fold(max_f(), 0)(2, 3, 5, 4) == 5);

    BOOST_HOF_STATIC_TEST_CHECK(boost::hof::fold(max_f(), 0)(2, 3, 4, 5) == 5);
    BOOST_HOF_STATIC_TEST_CHECK(boost::hof::fold(max_f(), 0)(5, 4, 3, 2) == 5);
    BOOST_HOF_STATIC_TEST_CHECK(boost::hof::fold(max_f(), 0)(2, 3, 5, 4) == 5);
}

BOOST_HOF_TEST_CASE()
{
    BOOST_HOF_TEST_CHECK(boost::hof::fold(max_f(), 0)() == 0);
    BOOST_HOF_TEST_CHECK(boost::hof::fold(max_f(), 0)(5) == 5);

    BOOST_HOF_STATIC_TEST_CHECK(boost::hof::fold(max_f(), 0)() == 0);
    BOOST_HOF_STATIC_TEST_CHECK(boost::hof::fold(max_f(), 0)(5) == 5);
}

template<class... Ts>
constexpr auto find_positive_max(Ts... xs) BOOST_HOF_RETURNS
(
    boost::hof::fold(max_f(), 0)(xs...)
);

BOOST_HOF_TEST_CASE()
{
    BOOST_HOF_TEST_CHECK(find_positive_max() == 0);
    BOOST_HOF_TEST_CHECK(find_positive_max(5) == 5);

    BOOST_HOF_STATIC_TEST_CHECK(find_positive_max() == 0);
    BOOST_HOF_STATIC_TEST_CHECK(find_positive_max(5) == 5);
}

BOOST_HOF_TEST_CASE()
{
    BOOST_HOF_TEST_CHECK(boost::hof::fold(max_f())(5) == 5);

    BOOST_HOF_STATIC_TEST_CHECK(boost::hof::fold(max_f())(5) == 5);
}

BOOST_HOF_TEST_CASE()
{
    BOOST_HOF_TEST_CHECK(boost::hof::fold(max_f())(2, 3, 4, 5) == 5);
    BOOST_HOF_TEST_CHECK(boost::hof::fold(max_f())(5, 4, 3, 2) == 5);
    BOOST_HOF_TEST_CHECK(boost::hof::fold(max_f())(2, 3, 5, 4) == 5);

    BOOST_HOF_STATIC_TEST_CHECK(boost::hof::fold(max_f())(2, 3, 4, 5) == 5);
    BOOST_HOF_STATIC_TEST_CHECK(boost::hof::fold(max_f())(5, 4, 3, 2) == 5);
    BOOST_HOF_STATIC_TEST_CHECK(boost::hof::fold(max_f())(2, 3, 5, 4) == 5);
}

BOOST_HOF_TEST_CASE()
{
    BOOST_HOF_TEST_CHECK(boost::hof::fold(sum_f(), std::string())("hello", "-", "world") == "hello-world");
}