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Diffstat (limited to 'third_party/abseil_cpp/absl/status/statusor.h')
| -rw-r--r-- | third_party/abseil_cpp/absl/status/statusor.h | 394 |
1 files changed, 0 insertions, 394 deletions
diff --git a/third_party/abseil_cpp/absl/status/statusor.h b/third_party/abseil_cpp/absl/status/statusor.h deleted file mode 100644 index 59a52cb782..0000000000 --- a/third_party/abseil_cpp/absl/status/statusor.h +++ /dev/null @@ -1,394 +0,0 @@ -/* Copyright 2017 The TensorFlow Authors. All Rights Reserved. - -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 - - http://www.apache.org/licenses/LICENSE-2.0 - -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. -==============================================================================*/ - -// StatusOr<T> is the union of a Status object and a T object. StatusOr models -// the concept of an object that is either a value, or an error Status -// explaining why such a value is not present. To this end, StatusOr<T> does not -// allow its Status value to be StatusCode::kOk. -// -// The primary use-case for StatusOr<T> is as the return value of a -// function which may fail. -// -// Example client usage for a StatusOr<T>, where T is not a pointer: -// -// StatusOr<float> result = DoBigCalculationThatCouldFail(); -// if (result.ok()) { -// float answer = result.ValueOrDie(); -// printf("Big calculation yielded: %f", answer); -// } else { -// LOG(ERROR) << result.status(); -// } -// -// Example client usage for a StatusOr<T*>: -// -// StatusOr<Foo*> result = FooFactory::MakeNewFoo(arg); -// if (result.ok()) { -// std::unique_ptr<Foo> foo(result.ValueOrDie()); -// foo->DoSomethingCool(); -// } else { -// LOG(ERROR) << result.status(); -// } -// -// Example client usage for a StatusOr<std::unique_ptr<T>>: -// -// StatusOr<std::unique_ptr<Foo>> result = FooFactory::MakeNewFoo(arg); -// if (result.ok()) { -// std::unique_ptr<Foo> foo = std::move(result.ValueOrDie()); -// foo->DoSomethingCool(); -// } else { -// LOG(ERROR) << result.status(); -// } -// -// Example factory implementation returning StatusOr<T*>: -// -// StatusOr<Foo*> FooFactory::MakeNewFoo(int arg) { -// if (arg <= 0) { -// return absl::InvalidArgumentError("Arg must be positive"); -// } else { -// return new Foo(arg); -// } -// } -// -// Note that the assignment operators require that destroying the currently -// stored value cannot invalidate the argument; in other words, the argument -// cannot be an alias for the current value, or anything owned by the current -// value. -#ifndef ABSL_STATUS_STATUSOR_H_ -#define ABSL_STATUS_STATUSOR_H_ - -#include "absl/status/status.h" -#include "absl/status/statusor_internals.h" - -namespace absl { -ABSL_NAMESPACE_BEGIN - -template <typename T> -class StatusOr : private internal_statusor::StatusOrData<T>, - private internal_statusor::TraitsBase< - std::is_copy_constructible<T>::value, - std::is_move_constructible<T>::value> { - template <typename U> - friend class StatusOr; - - typedef internal_statusor::StatusOrData<T> Base; - - public: - typedef T element_type; // DEPRECATED: use `value_type`. - typedef T value_type; - - // Constructs a new StatusOr with Status::UNKNOWN status. This is marked - // 'explicit' to try to catch cases like 'return {};', where people think - // StatusOr<std::vector<int>> will be initialized with an empty vector, - // instead of a Status::UNKNOWN status. - explicit StatusOr(); - - // StatusOr<T> will be copy constructible/assignable if T is copy - // constructible. - StatusOr(const StatusOr&) = default; - StatusOr& operator=(const StatusOr&) = default; - - // StatusOr<T> will be move constructible/assignable if T is move - // constructible. - StatusOr(StatusOr&&) = default; - StatusOr& operator=(StatusOr&&) = default; - - // Conversion copy/move constructor, T must be convertible from U. - template <typename U, typename std::enable_if< - std::is_convertible<U, T>::value>::type* = nullptr> - StatusOr(const StatusOr<U>& other); - template <typename U, typename std::enable_if< - std::is_convertible<U, T>::value>::type* = nullptr> - StatusOr(StatusOr<U>&& other); - - // Conversion copy/move assignment operator, T must be convertible from U. - template <typename U, typename std::enable_if< - std::is_convertible<U, T>::value>::type* = nullptr> - StatusOr& operator=(const StatusOr<U>& other); - template <typename U, typename std::enable_if< - std::is_convertible<U, T>::value>::type* = nullptr> - StatusOr& operator=(StatusOr<U>&& other); - - // Constructs a new StatusOr with the given value. After calling this - // constructor, calls to ValueOrDie() will succeed, and calls to status() will - // return OK. - // - // NOTE: Not explicit - we want to use StatusOr<T> as a return type - // so it is convenient and sensible to be able to do 'return T()' - // when the return type is StatusOr<T>. - // - // REQUIRES: T is copy constructible. - StatusOr(const T& value); - - // Constructs a new StatusOr with the given non-ok status. After calling - // this constructor, calls to ValueOrDie() will CHECK-fail. - // - // NOTE: Not explicit - we want to use StatusOr<T> as a return - // value, so it is convenient and sensible to be able to do 'return - // Status()' when the return type is StatusOr<T>. - // - // REQUIRES: !status.ok(). This requirement is enforced with either an - // exception (the passed absl::Status) or a FATAL log. - StatusOr(const Status& status); - StatusOr& operator=(const Status& status); - - // TODO(b/62186997): Add operator=(T) overloads. - - // Similar to the `const T&` overload. - // - // REQUIRES: T is move constructible. - StatusOr(T&& value); - - // RValue versions of the operations declared above. - StatusOr(Status&& status); - StatusOr& operator=(Status&& status); - - // Returns this->status().ok() - bool ok() const { return this->status_.ok(); } - - // Returns a reference to our status. If this contains a T, then - // returns OkStatus(). - const Status& status() const &; - Status status() &&; - - // Returns a reference to our current value, or CHECK-fails if !this->ok(). - // - // Note: for value types that are cheap to copy, prefer simple code: - // - // T value = statusor.ValueOrDie(); - // - // Otherwise, if the value type is expensive to copy, but can be left - // in the StatusOr, simply assign to a reference: - // - // T& value = statusor.ValueOrDie(); // or `const T&` - // - // Otherwise, if the value type supports an efficient move, it can be - // used as follows: - // - // T value = std::move(statusor).ValueOrDie(); - // - // The std::move on statusor instead of on the whole expression enables - // warnings about possible uses of the statusor object after the move. - // C++ style guide waiver for ref-qualified overloads granted in cl/143176389 - // See go/ref-qualifiers for more details on such overloads. - const T& ValueOrDie() const &; - T& ValueOrDie() &; - const T&& ValueOrDie() const &&; - T&& ValueOrDie() &&; - - // Returns a reference to the current value. - // - // REQUIRES: this->ok() == true, otherwise the behavior is undefined. - // - // Use this->ok() or `operator bool()` to verify that there is a current - // value. Alternatively, see ValueOrDie() for a similar API that guarantees - // CHECK-failing if there is no current value. - const T& operator*() const&; - T& operator*() &; - const T&& operator*() const&&; - T&& operator*() &&; - - // Returns a pointer to the current value. - // - // REQUIRES: this->ok() == true, otherwise the behavior is undefined. - // - // Use this->ok() or `operator bool()` to verify that there is a current - // value. - const T* operator->() const; - T* operator->(); - - T ConsumeValueOrDie() { return std::move(ValueOrDie()); } - - // Ignores any errors. This method does nothing except potentially suppress - // complaints from any tools that are checking that errors are not dropped on - // the floor. - void IgnoreError() const; -}; - -//////////////////////////////////////////////////////////////////////////////// -// Implementation details for StatusOr<T> - -template <typename T> -StatusOr<T>::StatusOr() : Base(Status(StatusCode::kUnknown, "")) {} - -template <typename T> -StatusOr<T>::StatusOr(const T& value) : Base(value) {} - -template <typename T> -StatusOr<T>::StatusOr(const Status& status) : Base(status) {} - -template <typename T> -StatusOr<T>& StatusOr<T>::operator=(const Status& status) { - this->Assign(status); - return *this; -} - -template <typename T> -StatusOr<T>::StatusOr(T&& value) : Base(std::move(value)) {} - -template <typename T> -StatusOr<T>::StatusOr(Status&& status) : Base(std::move(status)) {} - -template <typename T> -StatusOr<T>& StatusOr<T>::operator=(Status&& status) { - this->Assign(std::move(status)); - return *this; -} - -template <typename T> -template <typename U, - typename std::enable_if<std::is_convertible<U, T>::value>::type*> -inline StatusOr<T>::StatusOr(const StatusOr<U>& other) - : Base(static_cast<const typename StatusOr<U>::Base&>(other)) {} - -template <typename T> -template <typename U, - typename std::enable_if<std::is_convertible<U, T>::value>::type*> -inline StatusOr<T>& StatusOr<T>::operator=(const StatusOr<U>& other) { - if (other.ok()) - this->Assign(other.ValueOrDie()); - else - this->Assign(other.status()); - return *this; -} - -template <typename T> -template <typename U, - typename std::enable_if<std::is_convertible<U, T>::value>::type*> -inline StatusOr<T>::StatusOr(StatusOr<U>&& other) - : Base(static_cast<typename StatusOr<U>::Base&&>(other)) {} - -template <typename T> -template <typename U, - typename std::enable_if<std::is_convertible<U, T>::value>::type*> -inline StatusOr<T>& StatusOr<T>::operator=(StatusOr<U>&& other) { - if (other.ok()) { - this->Assign(std::move(other).ValueOrDie()); - } else { - this->Assign(std::move(other).status()); - } - return *this; -} - -template <typename T> -const Status& StatusOr<T>::status() const & { - return this->status_; -} -template <typename T> -Status StatusOr<T>::status() && { - // Note that we copy instead of moving the status here so that - // ~StatusOrData() can call ok() without invoking UB. - return ok() ? OkStatus() : this->status_; -} - -template <typename T> -const T& StatusOr<T>::ValueOrDie() const & { - this->EnsureOk(); - return this->data_; -} - -template <typename T> -T& StatusOr<T>::ValueOrDie() & { - this->EnsureOk(); - return this->data_; -} - -template <typename T> -const T&& StatusOr<T>::ValueOrDie() const && { - this->EnsureOk(); - return std::move(this->data_); -} - -template <typename T> -T&& StatusOr<T>::ValueOrDie() && { - this->EnsureOk(); - return std::move(this->data_); -} - -template <typename T> -const T* StatusOr<T>::operator->() const { - this->EnsureOk(); - return &this->data_; -} - -template <typename T> -T* StatusOr<T>::operator->() { - this->EnsureOk(); - return &this->data_; -} - -template <typename T> -const T& StatusOr<T>::operator*() const& { - this->EnsureOk(); - return this->data_; -} - -template <typename T> -T& StatusOr<T>::operator*() & { - this->EnsureOk(); - return this->data_; -} - -template <typename T> -const T&& StatusOr<T>::operator*() const&& { - this->EnsureOk(); - return std::move(this->data_); -} - -template <typename T> -T&& StatusOr<T>::operator*() && { - this->EnsureOk(); - return std::move(this->data_); -} - -template <typename T> -void StatusOr<T>::IgnoreError() const { - // no-op -} - -ABSL_NAMESPACE_END -} // namespace absl - -#define ASSERT_OK_AND_ASSIGN(lhs, rexpr) \ - ABSL_ASSERT_OK_AND_ASSIGN_IMPL( \ - ABSL_STATUS_MACROS_CONCAT_NAME(_status_or_value, __COUNTER__), lhs, \ - rexpr); - -#define ABSL_ASSERT_OK_AND_ASSIGN_IMPL(statusor, lhs, rexpr) \ - auto statusor = (rexpr); \ - ASSERT_TRUE(statusor.status().ok()) << statusor.status(); \ - lhs = std::move(statusor.ValueOrDie()) - -#define ABSL_STATUS_MACROS_CONCAT_NAME(x, y) ABSL_STATUS_MACROS_CONCAT_IMPL(x, y) -#define ABSL_STATUS_MACROS_CONCAT_IMPL(x, y) x##y - -#define ASSIGN_OR_RETURN(lhs, rexpr) \ - ABSL_ASSIGN_OR_RETURN_IMPL( \ - ABSL_STATUS_MACROS_CONCAT_NAME(_status_or_value, __COUNTER__), lhs, rexpr) - -#define ABSL_ASSIGN_OR_RETURN_IMPL(statusor, lhs, rexpr) \ - auto statusor = (rexpr); \ - if (ABSL_PREDICT_FALSE(!statusor.ok())) { \ - return statusor.status(); \ - } \ - lhs = std::move(statusor.ValueOrDie()) - -#define RETURN_IF_ERROR(status) \ - do { \ - if (ABSL_PREDICT_FALSE(!status.ok())) { \ - return status; \ - } \ - } while(0) - -#endif // ABSL_STATUS_STATUSOR_H_ |