///
//===----------------------------------------------------------------------===//
-#ifndef LLVM_SUPPORT_ERROR_OR_H
-#define LLVM_SUPPORT_ERROR_OR_H
+#ifndef LLVM_SUPPORT_ERROROR_H
+#define LLVM_SUPPORT_ERROROR_H
#include "llvm/ADT/PointerIntPair.h"
#include "llvm/Support/AlignOf.h"
-#include "llvm/Support/system_error.h"
-#include "llvm/Support/type_traits.h"
#include <cassert>
-#if LLVM_HAS_CXX11_TYPETRAITS
+#include <system_error>
#include <type_traits>
-#endif
namespace llvm {
-#if LLVM_HAS_CXX11_TYPETRAITS && LLVM_HAS_RVALUE_REFERENCES
template<class T, class V>
typename std::enable_if< std::is_constructible<T, V>::value
, typename std::remove_reference<V>::type>::type &&
moveIfMoveConstructible(V &Val) {
return Val;
}
-#else
-template<class T, class V>
-V &moveIfMoveConstructible(V &Val) {
- return Val;
-}
-#endif
/// \brief Stores a reference that can be changed.
template <typename T>
/// It is used like the following.
/// \code
/// ErrorOr<Buffer> getBuffer();
-/// void handleError(error_code ec);
///
/// auto buffer = getBuffer();
-/// if (!buffer)
-/// handleError(buffer);
+/// if (error_code ec = buffer.getError())
+/// return ec;
/// buffer->write("adena");
/// \endcode
///
template<class T>
class ErrorOr {
template <class OtherT> friend class ErrorOr;
- static const bool isRef = is_reference<T>::value;
- typedef ReferenceStorage<typename remove_reference<T>::type> wrap;
+ static const bool isRef = std::is_reference<T>::value;
+ typedef ReferenceStorage<typename std::remove_reference<T>::type> wrap;
public:
- typedef typename
- conditional< isRef
- , wrap
- , T
- >::type storage_type;
+ typedef typename std::conditional<isRef, wrap, T>::type storage_type;
private:
- typedef typename remove_reference<T>::type &reference;
- typedef typename remove_reference<T>::type *pointer;
+ typedef typename std::remove_reference<T>::type &reference;
+ typedef const typename std::remove_reference<T>::type &const_reference;
+ typedef typename std::remove_reference<T>::type *pointer;
public:
template <class E>
- ErrorOr(E ErrorCode, typename enable_if_c<is_error_code_enum<E>::value ||
- is_error_condition_enum<E>::value,
- void *>::type = 0)
+ ErrorOr(E ErrorCode,
+ typename std::enable_if<std::is_error_code_enum<E>::value ||
+ std::is_error_condition_enum<E>::value,
+ void *>::type = 0)
: HasError(true) {
- new (getError()) error_code(make_error_code(ErrorCode));
+ new (getErrorStorage()) std::error_code(make_error_code(ErrorCode));
}
- ErrorOr(llvm::error_code EC) : HasError(true) {
- new (getError()) error_code(EC);
+ ErrorOr(std::error_code EC) : HasError(true) {
+ new (getErrorStorage()) std::error_code(EC);
}
ErrorOr(T Val) : HasError(false) {
- new (get()) storage_type(moveIfMoveConstructible<storage_type>(Val));
+ new (getStorage()) storage_type(moveIfMoveConstructible<storage_type>(Val));
}
ErrorOr(const ErrorOr &Other) {
return *this;
}
-#if LLVM_HAS_RVALUE_REFERENCES
ErrorOr(ErrorOr &&Other) {
moveConstruct(std::move(Other));
}
moveAssign(std::move(Other));
return *this;
}
-#endif
~ErrorOr() {
if (!HasError)
- get()->~storage_type();
+ getStorage()->~storage_type();
}
- typedef void (*unspecified_bool_type)();
- static void unspecified_bool_true() {}
-
/// \brief Return false if there is an error.
- operator unspecified_bool_type() const {
- return HasError ? 0 : unspecified_bool_true;
+ LLVM_EXPLICIT operator bool() const {
+ return !HasError;
}
- operator llvm::error_code() const {
- return HasError ? *getError() : llvm::error_code::success();
+ reference get() { return *getStorage(); }
+ const_reference get() const { return const_cast<ErrorOr<T> >(this)->get(); }
+
+ std::error_code getError() const {
+ return HasError ? *getErrorStorage() : std::error_code();
}
pointer operator ->() {
- return toPointer(get());
+ return toPointer(getStorage());
}
reference operator *() {
- return *get();
+ return *getStorage();
}
private:
if (!Other.HasError) {
// Get the other value.
HasError = false;
- new (get()) storage_type(*Other.get());
+ new (getStorage()) storage_type(*Other.getStorage());
} else {
// Get other's error.
HasError = true;
- new (getError()) error_code(Other);
+ new (getErrorStorage()) std::error_code(Other.getError());
}
}
new (this) ErrorOr(Other);
}
-#if LLVM_HAS_RVALUE_REFERENCES
template <class OtherT>
void moveConstruct(ErrorOr<OtherT> &&Other) {
if (!Other.HasError) {
// Get the other value.
HasError = false;
- new (get()) storage_type(std::move(*Other.get()));
+ new (getStorage()) storage_type(std::move(*Other.getStorage()));
} else {
// Get other's error.
HasError = true;
- new (getError()) error_code(Other);
+ new (getErrorStorage()) std::error_code(Other.getError());
}
}
this->~ErrorOr();
new (this) ErrorOr(std::move(Other));
}
-#endif
pointer toPointer(pointer Val) {
return Val;
return &Val->get();
}
- storage_type *get() {
+ storage_type *getStorage() {
assert(!HasError && "Cannot get value when an error exists!");
return reinterpret_cast<storage_type*>(TStorage.buffer);
}
- const storage_type *get() const {
+ const storage_type *getStorage() const {
assert(!HasError && "Cannot get value when an error exists!");
return reinterpret_cast<const storage_type*>(TStorage.buffer);
}
- error_code *getError() {
+ std::error_code *getErrorStorage() {
assert(HasError && "Cannot get error when a value exists!");
- return reinterpret_cast<error_code*>(ErrorStorage.buffer);
+ return reinterpret_cast<std::error_code *>(ErrorStorage.buffer);
}
- const error_code *getError() const {
- return const_cast<ErrorOr<T> *>(this)->getError();
+ const std::error_code *getErrorStorage() const {
+ return const_cast<ErrorOr<T> *>(this)->getErrorStorage();
}
union {
AlignedCharArrayUnion<storage_type> TStorage;
- AlignedCharArrayUnion<error_code> ErrorStorage;
+ AlignedCharArrayUnion<std::error_code> ErrorStorage;
};
bool HasError : 1;
};
-template<class T, class E>
-typename enable_if_c<is_error_code_enum<E>::value ||
- is_error_condition_enum<E>::value, bool>::type
-operator ==(ErrorOr<T> &Err, E Code) {
- return error_code(Err) == Code;
+template <class T, class E>
+typename std::enable_if<std::is_error_code_enum<E>::value ||
+ std::is_error_condition_enum<E>::value,
+ bool>::type
+operator==(ErrorOr<T> &Err, E Code) {
+ return std::error_code(Err) == Code;
}
} // end namespace llvm