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-rwxr-xr-xzen/optional.h200
1 files changed, 100 insertions, 100 deletions
diff --git a/zen/optional.h b/zen/optional.h
index a4c67984..0efc34fe 100755
--- a/zen/optional.h
+++ b/zen/optional.h
@@ -1,100 +1,100 @@
-// *****************************************************************************
-// * This file is part of the FreeFileSync project. It is distributed under *
-// * GNU General Public License: http://www.gnu.org/licenses/gpl-3.0 *
-// * Copyright (C) Zenju (zenju AT freefilesync DOT org) - All Rights Reserved *
-// *****************************************************************************
-
-#ifndef OPTIONAL_H_2857428578342203589
-#define OPTIONAL_H_2857428578342203589
-
-#include <cassert>
-#include <type_traits>
-
-namespace zen
-{
-/*
-Optional return value without heap memory allocation!
- -> interface like a pointer, performance like a value
-
- Usage:
- ------
- Opt<MyEnum> someFunction();
-{
- if (allIsWell)
- return enumVal;
- else
- return NoValue();
-}
-
- Opt<MyEnum> optValue = someFunction();
- if (optValue)
- ... use *optValue ...
-*/
-
-struct NoValue {};
-
-template <class T>
-class Opt
-{
-public:
- Opt() {}
- Opt(NoValue) {}
- Opt(const T& val) : valid_(true) { new (&rawMem_) T(val); } //throw X
- Opt( T&& tmp) : valid_(true) { new (&rawMem_) T(std::move(tmp)); }
-
- Opt(const Opt& other) : valid_(other.valid_)
- {
- if (const T* val = other.get())
- new (&rawMem_) T(*val); //throw X
- }
-
- ~Opt() { if (T* val = get()) val->~T(); }
-
- Opt& operator=(NoValue) //support assignment to Opt<const T>
- {
- if (T* val = get())
- {
- valid_ = false;
- val->~T();
- }
- return *this;
- }
-
- Opt& operator=(const Opt& other) //strong exception-safety iff T::operator=() is strongly exception-safe
- {
- if (T* val = get())
- {
- if (const T* valOther = other.get())
- *val = *valOther; //throw X
- else
- {
- valid_ = false;
- val->~T();
- }
- }
- else if (const T* valOther = other.get())
- {
- new (&rawMem_) T(*valOther); //throw X
- valid_ = true;
- }
- return *this;
- }
-
- explicit operator bool() const { return valid_; } //thank you, C++11!!!
-
- const T* get() const { return valid_ ? reinterpret_cast<const T*>(&rawMem_) : nullptr; }
- T* get() { return valid_ ? reinterpret_cast< T*>(&rawMem_) : nullptr; }
-
- const T& operator*() const { return *get(); }
- /**/ T& operator*() { return *get(); }
-
- const T* operator->() const { return get(); }
- /**/ T* operator->() { return get(); }
-
-private:
- std::aligned_storage_t<sizeof(T), alignof(T)> rawMem_; //don't require T to be default-constructible!
- bool valid_ = false;
-};
-}
-
-#endif //OPTIONAL_H_2857428578342203589
+// *****************************************************************************
+// * This file is part of the FreeFileSync project. It is distributed under *
+// * GNU General Public License: http://www.gnu.org/licenses/gpl-3.0 *
+// * Copyright (C) Zenju (zenju AT freefilesync DOT org) - All Rights Reserved *
+// *****************************************************************************
+
+#ifndef OPTIONAL_H_2857428578342203589
+#define OPTIONAL_H_2857428578342203589
+
+#include <cassert>
+#include <type_traits>
+
+namespace zen
+{
+/*
+Optional return value without heap memory allocation!
+ -> interface like a pointer, performance like a value
+
+ Usage:
+ ------
+ Opt<MyEnum> someFunction();
+{
+ if (allIsWell)
+ return enumVal;
+ else
+ return NoValue();
+}
+
+ Opt<MyEnum> optValue = someFunction();
+ if (optValue)
+ ... use *optValue ...
+*/
+
+struct NoValue {};
+
+template <class T>
+class Opt
+{
+public:
+ Opt() {}
+ Opt(NoValue) {}
+ Opt(const T& val) : valid_(true) { new (&rawMem_) T(val); } //throw X
+ Opt( T&& tmp) : valid_(true) { new (&rawMem_) T(std::move(tmp)); }
+
+ Opt(const Opt& other) : valid_(other.valid_)
+ {
+ if (const T* val = other.get())
+ new (&rawMem_) T(*val); //throw X
+ }
+
+ ~Opt() { if (T* val = get()) val->~T(); }
+
+ Opt& operator=(NoValue) //support assignment to Opt<const T>
+ {
+ if (T* val = get())
+ {
+ valid_ = false;
+ val->~T();
+ }
+ return *this;
+ }
+
+ Opt& operator=(const Opt& other) //strong exception-safety iff T::operator=() is strongly exception-safe
+ {
+ if (T* val = get())
+ {
+ if (const T* valOther = other.get())
+ *val = *valOther; //throw X
+ else
+ {
+ valid_ = false;
+ val->~T();
+ }
+ }
+ else if (const T* valOther = other.get())
+ {
+ new (&rawMem_) T(*valOther); //throw X
+ valid_ = true;
+ }
+ return *this;
+ }
+
+ explicit operator bool() const { return valid_; } //thank you, C++11!!!
+
+ const T* get() const { return valid_ ? reinterpret_cast<const T*>(&rawMem_) : nullptr; }
+ T* get() { return valid_ ? reinterpret_cast< T*>(&rawMem_) : nullptr; }
+
+ const T& operator*() const { return *get(); }
+ /**/ T& operator*() { return *get(); }
+
+ const T* operator->() const { return get(); }
+ /**/ T* operator->() { return get(); }
+
+private:
+ std::aligned_storage_t<sizeof(T), alignof(T)> rawMem_; //don't require T to be default-constructible!
+ bool valid_ = false;
+};
+}
+
+#endif //OPTIONAL_H_2857428578342203589
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