#include "llvm/Support/AlignOf.h"
#include "llvm/Support/Compiler.h"
#include <cassert>
-
-#if LLVM_HAS_RVALUE_REFERENCES
+#include <new>
#include <utility>
-#endif
namespace llvm {
AlignedCharArrayUnion<T> storage;
bool hasVal;
public:
+ typedef T value_type;
+
Optional(NoneType) : hasVal(false) {}
explicit Optional() : hasVal(false) {}
Optional(const T &y) : hasVal(true) {
new (storage.buffer) T(*O);
}
-#if LLVM_HAS_RVALUE_REFERENCES
Optional(T &&y) : hasVal(true) {
new (storage.buffer) T(std::forward<T>(y));
}
}
return *this;
}
-#endif
+
+ /// Create a new object by constructing it in place with the given arguments.
+ template<typename ...ArgTypes>
+ void emplace(ArgTypes &&...Args) {
+ reset();
+ hasVal = true;
+ new (storage.buffer) T(std::forward<ArgTypes>(Args)...);
+ }
static inline Optional create(const T* y) {
return y ? Optional(*y) : Optional();
const T& getValue() const LLVM_LVALUE_FUNCTION { assert(hasVal); return *getPointer(); }
T& getValue() LLVM_LVALUE_FUNCTION { assert(hasVal); return *getPointer(); }
- LLVM_EXPLICIT operator bool() const { return hasVal; }
+ explicit operator bool() const { return hasVal; }
bool hasValue() const { return hasVal; }
const T* operator->() const { return getPointer(); }
T* operator->() { return getPointer(); }
const T& operator*() const LLVM_LVALUE_FUNCTION { assert(hasVal); return *getPointer(); }
T& operator*() LLVM_LVALUE_FUNCTION { assert(hasVal); return *getPointer(); }
+ template <typename U>
+ LLVM_CONSTEXPR T getValueOr(U &&value) const LLVM_LVALUE_FUNCTION {
+ return hasValue() ? getValue() : std::forward<U>(value);
+ }
+
#if LLVM_HAS_RVALUE_REFERENCE_THIS
T&& getValue() && { assert(hasVal); return std::move(*getPointer()); }
T&& operator*() && { assert(hasVal); return std::move(*getPointer()); }
+
+ template <typename U>
+ T getValueOr(U &&value) && {
+ return hasValue() ? std::move(getValue()) : std::forward<U>(value);
+ }
#endif
};
template<typename T, typename U>
void operator==(const Optional<T> &X, const Optional<U> &Y);
+template<typename T>
+bool operator==(const Optional<T> &X, NoneType) {
+ return !X.hasValue();
+}
+
+template<typename T>
+bool operator==(NoneType, const Optional<T> &X) {
+ return X == None;
+}
+
+template<typename T>
+bool operator!=(const Optional<T> &X, NoneType) {
+ return !(X == None);
+}
+
+template<typename T>
+bool operator!=(NoneType, const Optional<T> &X) {
+ return X != None;
+}
/// \brief Poison comparison between two \c Optional objects. Clients needs to
/// explicitly compare the underlying values and account for empty \c Optional
/// objects.