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diff --git a/absl/flags/internal/type_erased.h b/absl/flags/internal/type_erased.h
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+//
+// Copyright 2019 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.
+
+#ifndef ABSL_FLAGS_INTERNAL_TYPE_ERASED_H_
+#define ABSL_FLAGS_INTERNAL_TYPE_ERASED_H_
+
+#include <string>
+
+#include "absl/flags/internal/commandlineflag.h"
+#include "absl/flags/internal/registry.h"
+
+// --------------------------------------------------------------------
+// Registry interfaces operating on type erased handles.
+
+namespace absl {
+inline namespace lts_2019_08_08 {
+namespace flags_internal {
+
+// If a flag named "name" exists, store its current value in *OUTPUT
+// and return true.  Else return false without changing *OUTPUT.
+// Thread-safe.
+bool GetCommandLineOption(absl::string_view name, std::string* value);
+
+// If a flag named "name" exists, store its information in *OUTPUT
+// and return true.  Else return false without changing *OUTPUT.
+// Thread-safe.
+bool GetCommandLineFlagInfo(absl::string_view name,
+                            CommandLineFlagInfo* OUTPUT);
+
+// Returns the CommandLineFlagInfo of the flagname.  exit() with an
+// error code if name not found.
+// Thread-safe.
+CommandLineFlagInfo GetCommandLineFlagInfoOrDie(absl::string_view name);
+
+// Set the value of the flag named "name" to value.  If successful,
+// returns true.  If not successful (e.g., the flag was not found or
+// the value is not a valid value), returns false.
+// Thread-safe.
+bool SetCommandLineOption(absl::string_view name, absl::string_view value);
+
+bool SetCommandLineOptionWithMode(absl::string_view name,
+                                  absl::string_view value,
+                                  FlagSettingMode set_mode);
+
+//-----------------------------------------------------------------------------
+
+// Returns true iff all of the following conditions are true:
+// (a) "name" names a registered flag
+// (b) "value" can be parsed succesfully according to the type of the flag
+// (c) parsed value passes any validator associated with the flag
+bool IsValidFlagValue(absl::string_view name, absl::string_view value);
+
+//-----------------------------------------------------------------------------
+
+// Returns true iff a flag named "name" was specified on the command line
+// (either directly, or via one of --flagfile or --fromenv or --tryfromenv).
+//
+// Any non-command-line modification of the flag does not affect the
+// result of this function.  So for example, if a flag was passed on
+// the command line but then reset via SET_FLAGS_DEFAULT, this
+// function will still return true.
+bool SpecifiedOnCommandLine(absl::string_view name);
+
+//-----------------------------------------------------------------------------
+
+// If a flag with specified "name" exists and has type T, store
+// its current value in *dst and return true.  Else return false
+// without touching *dst.  T must obey all of the requirements for
+// types passed to DEFINE_FLAG.
+template <typename T>
+inline bool GetByName(absl::string_view name, T* dst) {
+  CommandLineFlag* flag = flags_internal::FindCommandLineFlag(name);
+  if (!flag) return false;
+
+  if (auto val = flag->Get<T>()) {
+    *dst = *val;
+    return true;
+  }
+
+  return false;
+}
+
+}  // namespace flags_internal
+}  // inline namespace lts_2019_08_08
+}  // namespace absl
+
+#endif  // ABSL_FLAGS_INTERNAL_TYPE_ERASED_H_