Open Chinese Convert  1.1.1
A project for conversion between Traditional and Simplified Chinese
Optional.hpp
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2  * Open Chinese Convert
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4  * Copyright 2010-2014 Carbo Kuo <byvoid@byvoid.com>
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18 
19 #pragma once
20 
21 namespace opencc {
26 template <typename T> class Optional {
27 public:
31  Optional(T actual) : isNull(false), data(actual) {}
32 
36  bool IsNull() const { return isNull; }
37 
41  const T& Get() const { return data; }
42 
46  static Optional<T> Null() { return Optional(); }
47 
48 private:
49  Optional() : isNull(true) {}
50 
51  bool isNull;
52  T data;
53 };
54 
60 template <typename T> class Optional<T*> {
61 private:
62  Optional() : data(nullptr) {}
63 
64  typedef T* TPtr;
65  TPtr data;
66 
67 public:
68  Optional(TPtr actual) : data(actual) {}
69 
70  bool IsNull() const { return data == nullptr; }
71 
72  const TPtr& Get() const { return data; }
73 
74  static Optional<TPtr> Null() { return Optional(); }
75 };
76 } // namespace opencc
opencc::Optional::Optional
Optional(T actual)
The constructor of Optional.
Definition: Optional.hpp:31
opencc::Optional::Null
static Optional< T > Null()
Constructs a null instance.
Definition: Optional.hpp:46
opencc::Optional::Get
const T & Get() const
Returns the containing data of the instance.
Definition: Optional.hpp:41
opencc::Optional::IsNull
bool IsNull() const
Returns true if the instance is null.
Definition: Optional.hpp:36
opencc::Optional
A class that wraps type T into a nullable type.
Definition: Optional.hpp:26