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
|
/*=========================================================================
*
* Copyright NumFOCUS
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0.txt
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*=========================================================================*/
#ifndef itkBoolean_h
#define itkBoolean_h
namespace itk
{
/**
* \class Boolean
*
* \brief An alternative to bool for additional thread safety
*
* The class `Boolean` provides an alternative to `bool`. `std::vector<bool>` is not thread safe due to the possibility
* of multiple bits being packed together in the same memory location. std::vector<Boolean> does not have such a space
* optimization. std::vector<Boolean> is semantically like `std::vector<bool>`, but unlike `std::vector<bool>`, it does
* "avoid data races when the contents of the contained object in different elements in the same container [...] are
* modified concurrently", according to the C++ Standard, section [container.requirements.dataraces], "Container data
* races".
*
* \ingroup ITKCommon
*/
class Boolean
{
public:
/** Supports default construction */
constexpr Boolean() = default;
/** Supports implicit conversion from `bool`. */
constexpr Boolean(bool v)
: m_Value(v)
{}
/** Supports implicit conversion to `bool`. */
constexpr operator bool() const { return m_Value; }
private:
bool m_Value = false;
};
} // namespace itk
#endif
|
