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diff --git a/mfbt/TypeTraits.h b/mfbt/TypeTraits.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* Template-based metaprogramming and type-testing facilities. */
+
+#ifndef mozilla_TypeTraits_h
+#define mozilla_TypeTraits_h
+
+#include "mozilla/Types.h"
+
+#include <type_traits>
+#include <utility>
+
+/*
+ * These traits are approximate copies of the traits and semantics from C++11's
+ * <type_traits> header.  Don't add traits not in that header!  When all
+ * platforms provide that header, we can convert all users and remove this one.
+ */
+
+namespace mozilla {
+
+/* 20.9.4 Unary type traits [meta.unary] */
+
+/* 20.9.4.3 Type properties [meta.unary.prop] */
+
+/**
+ * Traits class for identifying POD types.  Until C++11 there's no automatic
+ * way to detect PODs, so for the moment this is done manually.  Users may
+ * define specializations of this class that inherit from std::true_type and
+ * std::false_type (or equivalently std::integral_constant<bool, true or
+ * false>, or conveniently from mozilla::IsPod for composite types) as needed to
+ * ensure correct IsPod behavior.
+ */
+template <typename T>
+struct IsPod : public std::false_type {};
+
+template <>
+struct IsPod<char> : std::true_type {};
+template <>
+struct IsPod<signed char> : std::true_type {};
+template <>
+struct IsPod<unsigned char> : std::true_type {};
+template <>
+struct IsPod<short> : std::true_type {};
+template <>
+struct IsPod<unsigned short> : std::true_type {};
+template <>
+struct IsPod<int> : std::true_type {};
+template <>
+struct IsPod<unsigned int> : std::true_type {};
+template <>
+struct IsPod<long> : std::true_type {};
+template <>
+struct IsPod<unsigned long> : std::true_type {};
+template <>
+struct IsPod<long long> : std::true_type {};
+template <>
+struct IsPod<unsigned long long> : std::true_type {};
+template <>
+struct IsPod<bool> : std::true_type {};
+template <>
+struct IsPod<float> : std::true_type {};
+template <>
+struct IsPod<double> : std::true_type {};
+template <>
+struct IsPod<wchar_t> : std::true_type {};
+template <>
+struct IsPod<char16_t> : std::true_type {};
+template <typename T>
+struct IsPod<T*> : std::true_type {};
+
+namespace detail {
+
+struct DoIsDestructibleImpl {
+  template <typename T, typename = decltype(std::declval<T&>().~T())>
+  static std::true_type test(int);
+  template <typename T>
+  static std::false_type test(...);
+};
+
+template <typename T>
+struct IsDestructibleImpl : public DoIsDestructibleImpl {
+  typedef decltype(test<T>(0)) Type;
+};
+
+}  // namespace detail
+
+/**
+ * IsDestructible determines whether a type has a public destructor.
+ *
+ * struct S0 {};                    // Implicit default destructor.
+ * struct S1 { ~S1(); };
+ * class C2 { ~C2(); };             // private destructor.
+ *
+ * mozilla::IsDestructible<S0>::value is true;
+ * mozilla::IsDestructible<S1>::value is true;
+ * mozilla::IsDestructible<C2>::value is false.
+ */
+template <typename T>
+struct IsDestructible : public detail::IsDestructibleImpl<T>::Type {};
+
+} /* namespace mozilla */
+
+#endif /* mozilla_TypeTraits_h */