summaryrefslogtreecommitdiff
path: root/tools/inspector_protocol/lib/Maybe_h.template
blob: 22cfac6b240befc0cc6c06264b03ef7e3cf7e0c4 (plain)
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
// This file is generated by Maybe_h.template.

// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef {{"_".join(config.protocol.namespace)}}_Maybe_h
#define {{"_".join(config.protocol.namespace)}}_Maybe_h

// This macro allows to test for the version of the GNU C++ compiler.
// Note that this also applies to compilers that masquerade as GCC,
// for example clang and the Intel C++ compiler for Linux.
// Use like:
//  #if IP_GNUC_PREREQ(4, 3, 1)
//   ...
//  #endif
#if defined(__GNUC__) && defined(__GNUC_MINOR__) && defined(__GNUC_PATCHLEVEL__)
#define IP_GNUC_PREREQ(major, minor, patchlevel)                      \
  ((__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) >= \
   ((major)*10000 + (minor)*100 + (patchlevel)))
#elif defined(__GNUC__) && defined(__GNUC_MINOR__)
#define IP_GNUC_PREREQ(major, minor, patchlevel) \
  ((__GNUC__ * 10000 + __GNUC_MINOR__ * 100) >=  \
   ((major)*10000 + (minor)*100 + (patchlevel)))
#else
#define IP_GNUC_PREREQ(major, minor, patchlevel) 0
#endif

#if defined(__mips64)
#define IP_TARGET_ARCH_MIPS64 1
#elif defined(__MIPSEB__) || defined(__MIPSEL__)
#define IP_TARGET_ARCH_MIPS 1
#endif

// Allowing the use of noexcept by removing the keyword on older compilers that
// do not support adding noexcept to default members.
#if ((IP_GNUC_PREREQ(4, 9, 0) && !defined(IP_TARGET_ARCH_MIPS) && \
      !defined(IP_TARGET_ARCH_MIPS64)) ||                         \
     (defined(__clang__) && __cplusplus > 201300L))
#define IP_NOEXCEPT noexcept
#else
#define IP_NOEXCEPT
#endif

//#include "Forward.h"

{% for namespace in config.protocol.namespace %}
namespace {{namespace}} {
{% endfor %}

template<typename T>
class Maybe {
public:
    Maybe() : m_value() { }
    Maybe(std::unique_ptr<T> value) : m_value(std::move(value)) { }
    Maybe(Maybe&& other) IP_NOEXCEPT : m_value(std::move(other.m_value)) {}
    void operator=(std::unique_ptr<T> value) { m_value = std::move(value); }
    T* fromJust() const { DCHECK(m_value); return m_value.get(); }
    T* fromMaybe(T* defaultValue) const { return m_value ? m_value.get() : defaultValue; }
    bool isJust() const { return !!m_value; }
    std::unique_ptr<T> takeJust() { DCHECK(m_value); return std::move(m_value); }
private:
    std::unique_ptr<T> m_value;
};

template<typename T>
class MaybeBase {
public:
    MaybeBase() : m_isJust(false) { }
    MaybeBase(T value) : m_isJust(true), m_value(value) { }
    MaybeBase(MaybeBase&& other) IP_NOEXCEPT
        : m_isJust(other.m_isJust),
          m_value(std::move(other.m_value)) {}
    void operator=(T value) { m_value = value; m_isJust = true; }
    T fromJust() const { DCHECK(m_isJust); return m_value; }
    T fromMaybe(const T& defaultValue) const { return m_isJust ? m_value : defaultValue; }
    bool isJust() const { return m_isJust; }
    T takeJust() { DCHECK(m_isJust); return m_value; }

protected:
    bool m_isJust;
    T m_value;
};

template<>
class Maybe<bool> : public MaybeBase<bool> {
public:
    Maybe() { m_value = false; }
    Maybe(bool value) : MaybeBase(value) { }
    Maybe(Maybe&& other) IP_NOEXCEPT : MaybeBase(std::move(other)) {}
    using MaybeBase::operator=;
};

template<>
class Maybe<int> : public MaybeBase<int> {
public:
    Maybe() { m_value = 0; }
    Maybe(int value) : MaybeBase(value) { }
    Maybe(Maybe&& other) IP_NOEXCEPT : MaybeBase(std::move(other)) {}
    using MaybeBase::operator=;
};

template<>
class Maybe<double> : public MaybeBase<double> {
public:
    Maybe() { m_value = 0; }
    Maybe(double value) : MaybeBase(value) { }
    Maybe(Maybe&& other) IP_NOEXCEPT : MaybeBase(std::move(other)) {}
    using MaybeBase::operator=;
};

template<>
class Maybe<String> : public MaybeBase<String> {
public:
    Maybe() { }
    Maybe(const String& value) : MaybeBase(value) { }
    Maybe(Maybe&& other) IP_NOEXCEPT : MaybeBase(std::move(other)) {}
    using MaybeBase::operator=;
};

template<>
class Maybe<Binary> : public MaybeBase<Binary> {
public:
    Maybe() { }
    Maybe(Binary value) : MaybeBase(value) { }
    Maybe(Maybe&& other) IP_NOEXCEPT : MaybeBase(std::move(other)) {}
    using MaybeBase::operator=;
};

{% for namespace in config.protocol.namespace %}
} // namespace {{namespace}}
{% endfor %}

#undef IP_GNUC_PREREQ
#undef IP_TARGET_ARCH_MIPS64
#undef IP_TARGET_ARCH_MIPS
#undef IP_NOEXCEPT

#endif // !defined({{"_".join(config.protocol.namespace)}}_Maybe_h)