about summary refs log tree commit diff
path: root/third_party/immer/immer/detail/arrays/no_capacity.hpp
blob: 9cb561e14bc19588ef18b5410bd89f3521c1092b (plain) (blame)
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
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
//
// immer: immutable data structures for C++
// Copyright (C) 2016, 2017, 2018 Juan Pedro Bolivar Puente
//
// This software is distributed under the Boost Software License, Version 1.0.
// See accompanying file LICENSE or copy at http://boost.org/LICENSE_1_0.txt
//

#pragma once

#include <immer/algorithm.hpp>
#include <immer/detail/arrays/node.hpp>

namespace immer {
namespace detail {
namespace arrays {

template <typename T, typename MemoryPolicy>
struct no_capacity
{
    using node_t = node<T, MemoryPolicy>;
    using edit_t = typename MemoryPolicy::transience_t::edit;
    using size_t = std::size_t;

    node_t* ptr;
    size_t size;

    static const no_capacity& empty()
    {
        static const no_capacity empty_{
            node_t::make_n(0),
            0,
        };
        return empty_;
    }

    no_capacity(node_t* p, size_t s)
        : ptr{p}
        , size{s}
    {}

    no_capacity(const no_capacity& other)
        : no_capacity{other.ptr, other.size}
    {
        inc();
    }

    no_capacity(no_capacity&& other)
        : no_capacity{empty()}
    {
        swap(*this, other);
    }

    no_capacity& operator=(const no_capacity& other)
    {
        auto next = other;
        swap(*this, next);
        return *this;
    }

    no_capacity& operator=(no_capacity&& other)
    {
        swap(*this, other);
        return *this;
    }

    friend void swap(no_capacity& x, no_capacity& y)
    {
        using std::swap;
        swap(x.ptr, y.ptr);
        swap(x.size, y.size);
    }

    ~no_capacity() { dec(); }

    void inc()
    {
        using immer::detail::get;
        ptr->refs().inc();
    }

    void dec()
    {
        using immer::detail::get;
        if (ptr->refs().dec())
            node_t::delete_n(ptr, size, size);
    }

    T* data() { return ptr->data(); }
    const T* data() const { return ptr->data(); }

    T* data_mut(edit_t e)
    {
        if (!ptr->can_mutate(e))
            ptr = node_t::copy_e(e, size, ptr, size);
        return data();
    }

    template <typename Iter,
              typename Sent,
              std::enable_if_t<is_forward_iterator_v<Iter> &&
                                   compatible_sentinel_v<Iter, Sent>,
                               bool> = true>
    static no_capacity from_range(Iter first, Sent last)
    {
        auto count = static_cast<size_t>(distance(first, last));
        if (count == 0)
            return empty();
        else
            return {
                node_t::copy_n(count, first, last),
                count,
            };
    }

    static no_capacity from_fill(size_t n, T v)
    {
        return {node_t::fill_n(n, v), n};
    }

    template <typename U>
    static no_capacity from_initializer_list(std::initializer_list<U> values)
    {
        using namespace std;
        return from_range(begin(values), end(values));
    }

    template <typename Fn>
    void for_each_chunk(Fn&& fn) const
    {
        std::forward<Fn>(fn)(data(), data() + size);
    }

    template <typename Fn>
    bool for_each_chunk_p(Fn&& fn) const
    {
        return std::forward<Fn>(fn)(data(), data() + size);
    }

    const T& get(std::size_t index) const { return data()[index]; }

    const T& get_check(std::size_t index) const
    {
        if (index >= size)
            throw std::out_of_range{"out of range"};
        return data()[index];
    }

    bool equals(const no_capacity& other) const
    {
        return ptr == other.ptr ||
               (size == other.size &&
                std::equal(data(), data() + size, other.data()));
    }

    no_capacity push_back(T value) const
    {
        auto p = node_t::copy_n(size + 1, ptr, size);
        try {
            new (p->data() + size) T{std::move(value)};
            return {p, size + 1};
        } catch (...) {
            node_t::delete_n(p, size, size + 1);
            throw;
        }
    }

    no_capacity assoc(std::size_t idx, T value) const
    {
        auto p = node_t::copy_n(size, ptr, size);
        try {
            p->data()[idx] = std::move(value);
            return {p, size};
        } catch (...) {
            node_t::delete_n(p, size, size);
            throw;
        }
    }

    template <typename Fn>
    no_capacity update(std::size_t idx, Fn&& op) const
    {
        auto p = node_t::copy_n(size, ptr, size);
        try {
            auto& elem = p->data()[idx];
            elem       = std::forward<Fn>(op)(std::move(elem));
            return {p, size};
        } catch (...) {
            node_t::delete_n(p, size, size);
            throw;
        }
    }

    no_capacity take(std::size_t sz) const
    {
        auto p = node_t::copy_n(sz, ptr, sz);
        return {p, sz};
    }
};

} // namespace arrays
} // namespace detail
} // namespace immer