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diff --git a/util/std_util.h b/util/std_util.h
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+++ b/util/std_util.h
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+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef UTIL_STD_UTIL_H_
+#define UTIL_STD_UTIL_H_
+
+#include <map>
+#include <string>
+
+#include "absl/algorithm/container.h"
+
+namespace openscreen {
+
+// std::basic_string::data() has no mutable overload prior to C++17 [1].
+// Hence this overload is provided.
+// Note: str[0] is safe even for empty strings, as they are guaranteed to be
+// null-terminated [2].
+//
+// [1] http://en.cppreference.com/w/cpp/string/basic_string/data
+// [2] http://en.cppreference.com/w/cpp/string/basic_string/operator_at
+template <typename CharT, typename Traits, typename Allocator>
+CharT* data(std::basic_string<CharT, Traits, Allocator>& str) {
+  return std::addressof(str[0]);
+}
+
+template <typename Key, typename Value>
+void RemoveValueFromMap(std::map<Key, Value*>* map, Value* value) {
+  for (auto it = map->begin(); it != map->end();) {
+    if (it->second == value) {
+      it = map->erase(it);
+    } else {
+      ++it;
+    }
+  }
+}
+
+template <typename ForwardIteratingContainer>
+bool AreElementsSortedAndUnique(const ForwardIteratingContainer& c) {
+  return absl::c_is_sorted(c) && (absl::c_adjacent_find(c) == c.end());
+}
+
+template <typename RandomAccessContainer>
+void SortAndDedupeElements(RandomAccessContainer* c) {
+  std::sort(c->begin(), c->end());
+  const auto new_end = std::unique(c->begin(), c->end());
+  c->erase(new_end, c->end());
+}
+
+}  // namespace openscreen
+
+#endif  // UTIL_STD_UTIL_H_