Index: llvm/include/llvm/Support/Error.h
===================================================================
--- llvm/include/llvm/Support/Error.h
+++ llvm/include/llvm/Support/Error.h
@@ -587,6 +587,20 @@
     return takeError();
   }
 
+  /// Returns \a takeError() after emplacing the held T into \p MaybeValue, or
+  /// resetting it if there is none.
+  template <class OtherT>
+  Error
+  emplaceInto(Optional<OtherT> &MaybeValue,
+              std::enable_if_t<std::is_constructible<OtherT, T &&>::value> * =
+                  nullptr) {
+    if (*this)
+      MaybeValue.emplace(std::move(get()));
+    else
+      MaybeValue.reset();
+    return takeError();
+  }
+
   /// Check that this Expected<T> is an error of type ErrT.
   template <typename ErrT> bool errorIsA() const {
     return HasError && (*getErrorStorage())->template isA<ErrT>();
Index: llvm/unittests/Support/ErrorTest.cpp
===================================================================
--- llvm/unittests/Support/ErrorTest.cpp
+++ llvm/unittests/Support/ErrorTest.cpp
@@ -1099,4 +1099,75 @@
   }
 }
 
+struct ConstructOnlyBox {
+  Optional<int> Box;
+
+  explicit ConstructOnlyBox(int I) : Box(I) {}
+  ConstructOnlyBox(ConstructOnlyBox &&) = default;
+
+  ConstructOnlyBox() = delete;
+  ConstructOnlyBox &operator=(ConstructOnlyBox &&) = delete;
+
+  operator MoveOnlyBox() const {
+    return Box ? MoveOnlyBox(*Box) : MoveOnlyBox();
+  }
+
+  bool operator==(const ConstructOnlyBox &RHS) const {
+    if (bool(Box) != bool(RHS.Box))
+      return false;
+    return Box ? *Box == *RHS.Box : false;
+  }
+};
+
+TEST(Error, emplaceInto) {
+  // Use ConstructOnlyBox as the T in Expected<T>. Extract it into an Optional.
+  auto make = [](int I) -> Expected<ConstructOnlyBox> {
+    return ConstructOnlyBox(I);
+  };
+  auto makeFailure = []() -> Expected<ConstructOnlyBox> {
+    return createAnyError();
+  };
+
+  {
+    Optional<ConstructOnlyBox> V;
+
+    // Failure with no prior value.
+    EXPECT_THAT_ERROR(makeFailure().emplaceInto(V), Failed());
+    EXPECT_EQ(None, V);
+
+    // Success with no prior value.
+    EXPECT_THAT_ERROR(make(5).emplaceInto(V), Succeeded());
+    EXPECT_EQ(ConstructOnlyBox(5), V);
+
+    // Success with an existing value.
+    EXPECT_THAT_ERROR(make(7).emplaceInto(V), Succeeded());
+    EXPECT_EQ(ConstructOnlyBox(7), V);
+
+    // Failure with an existing value.
+    EXPECT_THAT_ERROR(makeFailure().emplaceInto(V), Failed());
+    EXPECT_EQ(None, V);
+  }
+
+  // Check that this works with another T.
+  {
+    Optional<MoveOnlyBox> V;
+
+    // Failure with no prior value.
+    EXPECT_THAT_ERROR(makeFailure().emplaceInto(V), Failed());
+    EXPECT_EQ(None, V);
+
+    // Success with no prior value.
+    EXPECT_THAT_ERROR(make(5).emplaceInto(V), Succeeded());
+    EXPECT_EQ(MoveOnlyBox(5), V);
+
+    // Success with an existing value.
+    EXPECT_THAT_ERROR(make(7).emplaceInto(V), Succeeded());
+    EXPECT_EQ(MoveOnlyBox(7), V);
+
+    // Failure with an existing value.
+    EXPECT_THAT_ERROR(makeFailure().emplaceInto(V), Failed());
+    EXPECT_EQ(None, V);
+  }
+}
+
 } // namespace