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authorVincent Ambo <mail@tazj.in>2022-02-07T23·05+0300
committerclbot <clbot@tvl.fyi>2022-02-07T23·09+0000
commit5aa5d282eac56a21e74611c1cdbaa97bb5db2dca (patch)
tree8cc5dce8157a1470ff76719dd15d65f648a05522 /third_party/abseil_cpp/absl/status/statusor.h
parenta25675804c4f429fab5ee5201fe25e89865dfd13 (diff)
chore(3p/abseil_cpp): unvendor abseil_cpp r/3786
we weren't actually using these sources anymore, okay?

Change-Id: If701571d9716de308d3512e1eb22c35db0877a66
Reviewed-on: https://cl.tvl.fyi/c/depot/+/5248
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Autosubmit: tazjin <tazjin@tvl.su>
Diffstat (limited to 'third_party/abseil_cpp/absl/status/statusor.h')
-rw-r--r--third_party/abseil_cpp/absl/status/statusor.h760
1 files changed, 0 insertions, 760 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 469d486fdd2e..000000000000
--- a/third_party/abseil_cpp/absl/status/statusor.h
+++ /dev/null
@@ -1,760 +0,0 @@
-// Copyright 2020 The Abseil Authors.
-//
-// 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
-//
-//      https://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.
-//
-// -----------------------------------------------------------------------------
-// File: statusor.h
-// -----------------------------------------------------------------------------
-//
-// An `absl::StatusOr<T>` represents a union of an `absl::Status` object
-// and an object of type `T`. The `absl::StatusOr<T>` will either contain an
-// object of type `T` (indicating a successful operation), or an error (of type
-// `absl::Status`) explaining why such a value is not present.
-//
-// In general, check the success of an operation returning an
-// `absl::StatusOr<T>` like you would an `absl::Status` by using the `ok()`
-// member function.
-//
-// Example:
-//
-//   StatusOr<Foo> result = Calculation();
-//   if (result.ok()) {
-//     result->DoSomethingCool();
-//   } else {
-//     LOG(ERROR) << result.status();
-//   }
-#ifndef ABSL_STATUS_STATUSOR_H_
-#define ABSL_STATUS_STATUSOR_H_
-
-#include <exception>
-#include <initializer_list>
-#include <new>
-#include <string>
-#include <type_traits>
-#include <utility>
-
-#include "absl/base/attributes.h"
-#include "absl/meta/type_traits.h"
-#include "absl/status/internal/statusor_internal.h"
-#include "absl/status/status.h"
-#include "absl/types/variant.h"
-#include "absl/utility/utility.h"
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-
-// BadStatusOrAccess
-//
-// This class defines the type of object to throw (if exceptions are enabled),
-// when accessing the value of an `absl::StatusOr<T>` object that does not
-// contain a value. This behavior is analogous to that of
-// `std::bad_optional_access` in the case of accessing an invalid
-// `std::optional` value.
-//
-// Example:
-//
-// try {
-//   absl::StatusOr<int> v = FetchInt();
-//   DoWork(v.value());  // Accessing value() when not "OK" may throw
-// } catch (absl::BadStatusOrAccess& ex) {
-//   LOG(ERROR) << ex.status();
-// }
-class BadStatusOrAccess : public std::exception {
- public:
-  explicit BadStatusOrAccess(absl::Status status);
-  ~BadStatusOrAccess() override;
-
-  // BadStatusOrAccess::what()
-  //
-  // Returns the associated explanatory string of the `absl::StatusOr<T>`
-  // object's error code. This function only returns the string literal "Bad
-  // StatusOr Access" for cases when evaluating general exceptions.
-  //
-  // The pointer of this string is guaranteed to be valid until any non-const
-  // function is invoked on the exception object.
-  const char* what() const noexcept override;
-
-  // BadStatusOrAccess::status()
-  //
-  // Returns the associated `absl::Status` of the `absl::StatusOr<T>` object's
-  // error.
-  const absl::Status& status() const;
-
- private:
-  absl::Status status_;
-};
-
-// Returned StatusOr objects may not be ignored.
-template <typename T>
-class ABSL_MUST_USE_RESULT StatusOr;
-
-// absl::StatusOr<T>
-//
-// The `absl::StatusOr<T>` class template is a union of an `absl::Status` object
-// and an object of type `T`. The `absl::StatusOr<T>` models an object that is
-// either a usable object, or an error (of type `absl::Status`) explaining why
-// such an object is not present. An `absl::StatusOr<T>` is typically the return
-// value of a function which may fail.
-//
-// An `absl::StatusOr<T>` can never hold an "OK" status (an
-// `absl::StatusCode::kOk` value); instead, the presence of an object of type
-// `T` indicates success. Instead of checking for a `kOk` value, use the
-// `absl::StatusOr<T>::ok()` member function. (It is for this reason, and code
-// readability, that using the `ok()` function is preferred for `absl::Status`
-// as well.)
-//
-// Example:
-//
-//   StatusOr<Foo> result = DoBigCalculationThatCouldFail();
-//   if (result.ok()) {
-//     result->DoSomethingCool();
-//   } else {
-//     LOG(ERROR) << result.status();
-//   }
-//
-// Accessing the object held by an `absl::StatusOr<T>` should be performed via
-// `operator*` or `operator->`, after a call to `ok()` confirms that the
-// `absl::StatusOr<T>` holds an object of type `T`:
-//
-// Example:
-//
-//   absl::StatusOr<int> i = GetCount();
-//   if (i.ok()) {
-//     updated_total += *i
-//   }
-//
-// NOTE: using `absl::StatusOr<T>::value()` when no valid value is present will
-// throw an exception if exceptions are enabled or terminate the process when
-// execeptions are not enabled.
-//
-// Example:
-//
-//   StatusOr<Foo> result = DoBigCalculationThatCouldFail();
-//   const Foo& foo = result.value();    // Crash/exception if no value present
-//   foo.DoSomethingCool();
-//
-// A `absl::StatusOr<T*>` can be constructed from a null pointer like any other
-// pointer value, and the result will be that `ok()` returns `true` and
-// `value()` returns `nullptr`. Checking the value of pointer in an
-// `absl::StatusOr<T>` generally requires a bit more care, to ensure both that a
-// value is present and that value is not null:
-//
-//  StatusOr<std::unique_ptr<Foo>> result = FooFactory::MakeNewFoo(arg);
-//  if (!result.ok()) {
-//    LOG(ERROR) << result.status();
-//  } else if (*result == nullptr) {
-//    LOG(ERROR) << "Unexpected null pointer";
-//  } else {
-//    (*result)->DoSomethingCool();
-//  }
-//
-// Example factory implementation returning StatusOr<T>:
-//
-//  StatusOr<Foo> FooFactory::MakeFoo(int arg) {
-//    if (arg <= 0) {
-//      return absl::Status(absl::StatusCode::kInvalidArgument,
-//                          "Arg must be positive");
-//    }
-//    return Foo(arg);
-//  }
-template <typename T>
-class StatusOr : private internal_statusor::StatusOrData<T>,
-                 private internal_statusor::CopyCtorBase<T>,
-                 private internal_statusor::MoveCtorBase<T>,
-                 private internal_statusor::CopyAssignBase<T>,
-                 private internal_statusor::MoveAssignBase<T> {
-  template <typename U>
-  friend class StatusOr;
-
-  typedef internal_statusor::StatusOrData<T> Base;
-
- public:
-  // StatusOr<T>::value_type
-  //
-  // This instance data provides a generic `value_type` member for use within
-  // generic programming. This usage is analogous to that of
-  // `optional::value_type` in the case of `std::optional`.
-  typedef T value_type;
-
-  // Constructors
-
-  // Constructs a new `absl::StatusOr` with an `absl::StatusCode::kUnknown`
-  // status. This constructor is marked 'explicit' to prevent usages in return
-  // values such as 'return {};', under the misconception that
-  // `absl::StatusOr<std::vector<int>>` will be initialized with an empty
-  // vector, instead of an `absl::StatusCode::kUnknown` error code.
-  explicit StatusOr();
-
-  // `StatusOr<T>` is copy constructible if `T` is copy constructible.
-  StatusOr(const StatusOr&) = default;
-  // `StatusOr<T>` is copy assignable if `T` is copy constructible and copy
-  // assignable.
-  StatusOr& operator=(const StatusOr&) = default;
-
-  // `StatusOr<T>` is move constructible if `T` is move constructible.
-  StatusOr(StatusOr&&) = default;
-  // `StatusOr<T>` is moveAssignable if `T` is move constructible and move
-  // assignable.
-  StatusOr& operator=(StatusOr&&) = default;
-
-  // Converting Constructors
-
-  // Constructs a new `absl::StatusOr<T>` from an `absl::StatusOr<U>`, when `T`
-  // is constructible from `U`. To avoid ambiguity, these constructors are
-  // disabled if `T` is also constructible from `StatusOr<U>.`. This constructor
-  // is explicit if and only if the corresponding construction of `T` from `U`
-  // is explicit. (This constructor inherits its explicitness from the
-  // underlying constructor.)
-  template <
-      typename U,
-      absl::enable_if_t<
-          absl::conjunction<
-              absl::negation<std::is_same<T, U>>,
-              std::is_constructible<T, const U&>,
-              std::is_convertible<const U&, T>,
-              absl::negation<
-                  internal_statusor::IsConstructibleOrConvertibleFromStatusOr<
-                      T, U>>>::value,
-          int> = 0>
-  StatusOr(const StatusOr<U>& other)  // NOLINT
-      : Base(static_cast<const typename StatusOr<U>::Base&>(other)) {}
-  template <
-      typename U,
-      absl::enable_if_t<
-          absl::conjunction<
-              absl::negation<std::is_same<T, U>>,
-              std::is_constructible<T, const U&>,
-              absl::negation<std::is_convertible<const U&, T>>,
-              absl::negation<
-                  internal_statusor::IsConstructibleOrConvertibleFromStatusOr<
-                      T, U>>>::value,
-          int> = 0>
-  explicit StatusOr(const StatusOr<U>& other)
-      : Base(static_cast<const typename StatusOr<U>::Base&>(other)) {}
-
-  template <
-      typename U,
-      absl::enable_if_t<
-          absl::conjunction<
-              absl::negation<std::is_same<T, U>>, std::is_constructible<T, U&&>,
-              std::is_convertible<U&&, T>,
-              absl::negation<
-                  internal_statusor::IsConstructibleOrConvertibleFromStatusOr<
-                      T, U>>>::value,
-          int> = 0>
-  StatusOr(StatusOr<U>&& other)  // NOLINT
-      : Base(static_cast<typename StatusOr<U>::Base&&>(other)) {}
-  template <
-      typename U,
-      absl::enable_if_t<
-          absl::conjunction<
-              absl::negation<std::is_same<T, U>>, std::is_constructible<T, U&&>,
-              absl::negation<std::is_convertible<U&&, T>>,
-              absl::negation<
-                  internal_statusor::IsConstructibleOrConvertibleFromStatusOr<
-                      T, U>>>::value,
-          int> = 0>
-  explicit StatusOr(StatusOr<U>&& other)
-      : Base(static_cast<typename StatusOr<U>::Base&&>(other)) {}
-
-  // Converting Assignment Operators
-
-  // Creates an `absl::StatusOr<T>` through assignment from an
-  // `absl::StatusOr<U>` when:
-  //
-  //   * Both `absl::StatusOr<T>` and `absl::StatusOr<U>` are OK by assigning
-  //     `U` to `T` directly.
-  //   * `absl::StatusOr<T>` is OK and `absl::StatusOr<U>` contains an error
-  //      code by destroying `absl::StatusOr<T>`'s value and assigning from
-  //      `absl::StatusOr<U>'
-  //   * `absl::StatusOr<T>` contains an error code and `absl::StatusOr<U>` is
-  //      OK by directly initializing `T` from `U`.
-  //   * Both `absl::StatusOr<T>` and `absl::StatusOr<U>` contain an error
-  //     code by assigning the `Status` in `absl::StatusOr<U>` to
-  //     `absl::StatusOr<T>`
-  //
-  // These overloads only apply if `absl::StatusOr<T>` is constructible and
-  // assignable from `absl::StatusOr<U>` and `StatusOr<T>` cannot be directly
-  // assigned from `StatusOr<U>`.
-  template <
-      typename U,
-      absl::enable_if_t<
-          absl::conjunction<
-              absl::negation<std::is_same<T, U>>,
-              std::is_constructible<T, const U&>,
-              std::is_assignable<T, const U&>,
-              absl::negation<
-                  internal_statusor::
-                      IsConstructibleOrConvertibleOrAssignableFromStatusOr<
-                          T, U>>>::value,
-          int> = 0>
-  StatusOr& operator=(const StatusOr<U>& other) {
-    this->Assign(other);
-    return *this;
-  }
-  template <
-      typename U,
-      absl::enable_if_t<
-          absl::conjunction<
-              absl::negation<std::is_same<T, U>>, std::is_constructible<T, U&&>,
-              std::is_assignable<T, U&&>,
-              absl::negation<
-                  internal_statusor::
-                      IsConstructibleOrConvertibleOrAssignableFromStatusOr<
-                          T, U>>>::value,
-          int> = 0>
-  StatusOr& operator=(StatusOr<U>&& other) {
-    this->Assign(std::move(other));
-    return *this;
-  }
-
-  // Constructs a new `absl::StatusOr<T>` with a non-ok status. After calling
-  // this constructor, `this->ok()` will be `false` and calls to `value()` will
-  // crash, or produce an exception if exceptions are enabled.
-  //
-  // The constructor also takes any type `U` that is convertible to
-  // `absl::Status`. This constructor is explicit if an only if `U` is not of
-  // type `absl::Status` and the conversion from `U` to `Status` is explicit.
-  //
-  // REQUIRES: !Status(std::forward<U>(v)).ok(). This requirement is DCHECKed.
-  // In optimized builds, passing absl::OkStatus() here will have the effect
-  // of passing absl::StatusCode::kInternal as a fallback.
-  template <
-      typename U = absl::Status,
-      absl::enable_if_t<
-          absl::conjunction<
-              std::is_convertible<U&&, absl::Status>,
-              std::is_constructible<absl::Status, U&&>,
-              absl::negation<std::is_same<absl::decay_t<U>, absl::StatusOr<T>>>,
-              absl::negation<std::is_same<absl::decay_t<U>, T>>,
-              absl::negation<std::is_same<absl::decay_t<U>, absl::in_place_t>>,
-              absl::negation<internal_statusor::HasConversionOperatorToStatusOr<
-                  T, U&&>>>::value,
-          int> = 0>
-  StatusOr(U&& v) : Base(std::forward<U>(v)) {}
-
-  template <
-      typename U = absl::Status,
-      absl::enable_if_t<
-          absl::conjunction<
-              absl::negation<std::is_convertible<U&&, absl::Status>>,
-              std::is_constructible<absl::Status, U&&>,
-              absl::negation<std::is_same<absl::decay_t<U>, absl::StatusOr<T>>>,
-              absl::negation<std::is_same<absl::decay_t<U>, T>>,
-              absl::negation<std::is_same<absl::decay_t<U>, absl::in_place_t>>,
-              absl::negation<internal_statusor::HasConversionOperatorToStatusOr<
-                  T, U&&>>>::value,
-          int> = 0>
-  explicit StatusOr(U&& v) : Base(std::forward<U>(v)) {}
-
-  template <
-      typename U = absl::Status,
-      absl::enable_if_t<
-          absl::conjunction<
-              std::is_convertible<U&&, absl::Status>,
-              std::is_constructible<absl::Status, U&&>,
-              absl::negation<std::is_same<absl::decay_t<U>, absl::StatusOr<T>>>,
-              absl::negation<std::is_same<absl::decay_t<U>, T>>,
-              absl::negation<std::is_same<absl::decay_t<U>, absl::in_place_t>>,
-              absl::negation<internal_statusor::HasConversionOperatorToStatusOr<
-                  T, U&&>>>::value,
-          int> = 0>
-  StatusOr& operator=(U&& v) {
-    this->AssignStatus(std::forward<U>(v));
-    return *this;
-  }
-
-  // Perfect-forwarding value assignment operator.
-
-  // If `*this` contains a `T` value before the call, the contained value is
-  // assigned from `std::forward<U>(v)`; Otherwise, it is directly-initialized
-  // from `std::forward<U>(v)`.
-  // This function does not participate in overload unless:
-  // 1. `std::is_constructible_v<T, U>` is true,
-  // 2. `std::is_assignable_v<T&, U>` is true.
-  // 3. `std::is_same_v<StatusOr<T>, std::remove_cvref_t<U>>` is false.
-  // 4. Assigning `U` to `T` is not ambiguous:
-  //  If `U` is `StatusOr<V>` and `T` is constructible and assignable from
-  //  both `StatusOr<V>` and `V`, the assignment is considered bug-prone and
-  //  ambiguous thus will fail to compile. For example:
-  //    StatusOr<bool> s1 = true;  // s1.ok() && *s1 == true
-  //    StatusOr<bool> s2 = false;  // s2.ok() && *s2 == false
-  //    s1 = s2;  // ambiguous, `s1 = *s2` or `s1 = bool(s2)`?
-  template <
-      typename U = T,
-      typename = typename std::enable_if<absl::conjunction<
-          std::is_constructible<T, U&&>, std::is_assignable<T&, U&&>,
-          absl::disjunction<
-              std::is_same<absl::remove_cv_t<absl::remove_reference_t<U>>, T>,
-              absl::conjunction<
-                  absl::negation<std::is_convertible<U&&, absl::Status>>,
-                  absl::negation<internal_statusor::
-                                     HasConversionOperatorToStatusOr<T, U&&>>>>,
-          internal_statusor::IsForwardingAssignmentValid<T, U&&>>::value>::type>
-  StatusOr& operator=(U&& v) {
-    this->Assign(std::forward<U>(v));
-    return *this;
-  }
-
-  // Constructs the inner value `T` in-place using the provided args, using the
-  // `T(args...)` constructor.
-  template <typename... Args>
-  explicit StatusOr(absl::in_place_t, Args&&... args);
-  template <typename U, typename... Args>
-  explicit StatusOr(absl::in_place_t, std::initializer_list<U> ilist,
-                    Args&&... args);
-
-  // Constructs the inner value `T` in-place using the provided args, using the
-  // `T(U)` (direct-initialization) constructor. This constructor is only valid
-  // if `T` can be constructed from a `U`. Can accept move or copy constructors.
-  //
-  // This constructor is explicit if `U` is not convertible to `T`. To avoid
-  // ambiguity, this constuctor is disabled if `U` is a `StatusOr<J>`, where `J`
-  // is convertible to `T`.
-  template <
-      typename U = T,
-      absl::enable_if_t<
-          absl::conjunction<
-              internal_statusor::IsDirectInitializationValid<T, U&&>,
-              std::is_constructible<T, U&&>, std::is_convertible<U&&, T>,
-              absl::disjunction<
-                  std::is_same<absl::remove_cv_t<absl::remove_reference_t<U>>,
-                               T>,
-                  absl::conjunction<
-                      absl::negation<std::is_convertible<U&&, absl::Status>>,
-                      absl::negation<
-                          internal_statusor::HasConversionOperatorToStatusOr<
-                              T, U&&>>>>>::value,
-          int> = 0>
-  StatusOr(U&& u)  // NOLINT
-      : StatusOr(absl::in_place, std::forward<U>(u)) {
-  }
-
-  template <
-      typename U = T,
-      absl::enable_if_t<
-          absl::conjunction<
-              internal_statusor::IsDirectInitializationValid<T, U&&>,
-              absl::disjunction<
-                  std::is_same<absl::remove_cv_t<absl::remove_reference_t<U>>,
-                               T>,
-                  absl::conjunction<
-                      absl::negation<std::is_constructible<absl::Status, U&&>>,
-                      absl::negation<
-                          internal_statusor::HasConversionOperatorToStatusOr<
-                              T, U&&>>>>,
-              std::is_constructible<T, U&&>,
-              absl::negation<std::is_convertible<U&&, T>>>::value,
-          int> = 0>
-  explicit StatusOr(U&& u)  // NOLINT
-      : StatusOr(absl::in_place, std::forward<U>(u)) {
-  }
-
-  // StatusOr<T>::ok()
-  //
-  // Returns whether or not this `absl::StatusOr<T>` holds a `T` value. This
-  // member function is analagous to `absl::Status::ok()` and should be used
-  // similarly to check the status of return values.
-  //
-  // Example:
-  //
-  // StatusOr<Foo> result = DoBigCalculationThatCouldFail();
-  // if (result.ok()) {
-  //    // Handle result
-  // else {
-  //    // Handle error
-  // }
-  ABSL_MUST_USE_RESULT bool ok() const { return this->status_.ok(); }
-
-  // StatusOr<T>::status()
-  //
-  // Returns a reference to the current `absl::Status` contained within the
-  // `absl::StatusOr<T>`. If `absl::StatusOr<T>` contains a `T`, then this
-  // function returns `absl::OkStatus()`.
-  const Status& status() const &;
-  Status status() &&;
-
-  // StatusOr<T>::value()
-  //
-  // Returns a reference to the held value if `this->ok()`. Otherwise, throws
-  // `absl::BadStatusOrAccess` if exceptions are enabled, or is guaranteed to
-  // terminate the process if exceptions are disabled.
-  //
-  // If you have already checked the status using `this->ok()`, you probably
-  // want to use `operator*()` or `operator->()` to access the value instead of
-  // `value`.
-  //
-  // Note: for value types that are cheap to copy, prefer simple code:
-  //
-  //   T value = statusor.value();
-  //
-  // Otherwise, if the value type is expensive to copy, but can be left
-  // in the StatusOr, simply assign to a reference:
-  //
-  //   T& value = statusor.value();  // or `const T&`
-  //
-  // Otherwise, if the value type supports an efficient move, it can be
-  // used as follows:
-  //
-  //   T value = std::move(statusor).value();
-  //
-  // The `std::move` on statusor instead of on the whole expression enables
-  // warnings about possible uses of the statusor object after the move.
-  const T& value() const&;
-  T& value() &;
-  const T&& value() const&&;
-  T&& value() &&;
-
-  // StatusOr<T>:: operator*()
-  //
-  // Returns a reference to the current value.
-  //
-  // REQUIRES: `this->ok() == true`, otherwise the behavior is undefined.
-  //
-  // Use `this->ok()` to verify that there is a current value within the
-  // `absl::StatusOr<T>`. Alternatively, see the `value()` member function for a
-  // similar API that guarantees crashing or throwing an exception if there is
-  // no current value.
-  const T& operator*() const&;
-  T& operator*() &;
-  const T&& operator*() const&&;
-  T&& operator*() &&;
-
-  // StatusOr<T>::operator->()
-  //
-  // Returns a pointer to the current value.
-  //
-  // REQUIRES: `this->ok() == true`, otherwise the behavior is undefined.
-  //
-  // Use `this->ok()` to verify that there is a current value.
-  const T* operator->() const;
-  T* operator->();
-
-  // StatusOr<T>::value_or()
-  //
-  // Returns the current value if `this->ok() == true`. Otherwise constructs a
-  // value using the provided `default_value`.
-  //
-  // Unlike `value`, this function returns by value, copying the current value
-  // if necessary. If the value type supports an efficient move, it can be used
-  // as follows:
-  //
-  //   T value = std::move(statusor).value_or(def);
-  //
-  // Unlike with `value`, calling `std::move()` on the result of `value_or` will
-  // still trigger a copy.
-  template <typename U>
-  T value_or(U&& default_value) const&;
-  template <typename U>
-  T value_or(U&& default_value) &&;
-
-  // StatusOr<T>::IgnoreError()
-  //
-  // 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;
-
-  // StatusOr<T>::emplace()
-  //
-  // Reconstructs the inner value T in-place using the provided args, using the
-  // T(args...) constructor. Returns reference to the reconstructed `T`.
-  template <typename... Args>
-  T& emplace(Args&&... args) {
-    if (ok()) {
-      this->Clear();
-      this->MakeValue(std::forward<Args>(args)...);
-    } else {
-      this->MakeValue(std::forward<Args>(args)...);
-      this->status_ = absl::OkStatus();
-    }
-    return this->data_;
-  }
-
-  template <
-      typename U, typename... Args,
-      absl::enable_if_t<
-          std::is_constructible<T, std::initializer_list<U>&, Args&&...>::value,
-          int> = 0>
-  T& emplace(std::initializer_list<U> ilist, Args&&... args) {
-    if (ok()) {
-      this->Clear();
-      this->MakeValue(ilist, std::forward<Args>(args)...);
-    } else {
-      this->MakeValue(ilist, std::forward<Args>(args)...);
-      this->status_ = absl::OkStatus();
-    }
-    return this->data_;
-  }
-
- private:
-  using internal_statusor::StatusOrData<T>::Assign;
-  template <typename U>
-  void Assign(const absl::StatusOr<U>& other);
-  template <typename U>
-  void Assign(absl::StatusOr<U>&& other);
-};
-
-// operator==()
-//
-// This operator checks the equality of two `absl::StatusOr<T>` objects.
-template <typename T>
-bool operator==(const StatusOr<T>& lhs, const StatusOr<T>& rhs) {
-  if (lhs.ok() && rhs.ok()) return *lhs == *rhs;
-  return lhs.status() == rhs.status();
-}
-
-// operator!=()
-//
-// This operator checks the inequality of two `absl::StatusOr<T>` objects.
-template <typename T>
-bool operator!=(const StatusOr<T>& lhs, const StatusOr<T>& rhs) {
-  return !(lhs == rhs);
-}
-
-//------------------------------------------------------------------------------
-// Implementation details for StatusOr<T>
-//------------------------------------------------------------------------------
-
-// TODO(sbenza): avoid the string here completely.
-template <typename T>
-StatusOr<T>::StatusOr() : Base(Status(absl::StatusCode::kUnknown, "")) {}
-
-template <typename T>
-template <typename U>
-inline void StatusOr<T>::Assign(const StatusOr<U>& other) {
-  if (other.ok()) {
-    this->Assign(*other);
-  } else {
-    this->AssignStatus(other.status());
-  }
-}
-
-template <typename T>
-template <typename U>
-inline void StatusOr<T>::Assign(StatusOr<U>&& other) {
-  if (other.ok()) {
-    this->Assign(*std::move(other));
-  } else {
-    this->AssignStatus(std::move(other).status());
-  }
-}
-template <typename T>
-template <typename... Args>
-StatusOr<T>::StatusOr(absl::in_place_t, Args&&... args)
-    : Base(absl::in_place, std::forward<Args>(args)...) {}
-
-template <typename T>
-template <typename U, typename... Args>
-StatusOr<T>::StatusOr(absl::in_place_t, std::initializer_list<U> ilist,
-                      Args&&... args)
-    : Base(absl::in_place, ilist, std::forward<Args>(args)...) {}
-
-template <typename T>
-const Status& StatusOr<T>::status() const & { return this->status_; }
-template <typename T>
-Status StatusOr<T>::status() && {
-  return ok() ? OkStatus() : std::move(this->status_);
-}
-
-template <typename T>
-const T& StatusOr<T>::value() const& {
-  if (!this->ok()) internal_statusor::ThrowBadStatusOrAccess(this->status_);
-  return this->data_;
-}
-
-template <typename T>
-T& StatusOr<T>::value() & {
-  if (!this->ok()) internal_statusor::ThrowBadStatusOrAccess(this->status_);
-  return this->data_;
-}
-
-template <typename T>
-const T&& StatusOr<T>::value() const&& {
-  if (!this->ok()) {
-    internal_statusor::ThrowBadStatusOrAccess(std::move(this->status_));
-  }
-  return std::move(this->data_);
-}
-
-template <typename T>
-T&& StatusOr<T>::value() && {
-  if (!this->ok()) {
-    internal_statusor::ThrowBadStatusOrAccess(std::move(this->status_));
-  }
-  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 std::move(this->data_);
-}
-
-template <typename T>
-T&& StatusOr<T>::operator*() && {
-  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>
-template <typename U>
-T StatusOr<T>::value_or(U&& default_value) const& {
-  if (ok()) {
-    return this->data_;
-  }
-  return std::forward<U>(default_value);
-}
-
-template <typename T>
-template <typename U>
-T StatusOr<T>::value_or(U&& default_value) && {
-  if (ok()) {
-    return std::move(this->data_);
-  }
-  return std::forward<U>(default_value);
-}
-
-template <typename T>
-void StatusOr<T>::IgnoreError() const {
-  // no-op
-}
-
-ABSL_NAMESPACE_END
-}  // namespace absl
-
-#endif  // ABSL_STATUS_STATUSOR_H_