+template<typename T, typename Dp = std::default_delete<T>, typename... Args>
+typename std::enable_if<!std::is_array<T>::value, std::unique_ptr<T, Dp>>::type
+make_unique(Args&&... args) {
+ return std::unique_ptr<T, Dp>(new T(std::forward<Args>(args)...));
+}
+
+// Allows 'make_unique<T[]>(10)'. (N3690 s20.9.1.4 p3-4)
+template<typename T, typename Dp = std::default_delete<T>>
+typename std::enable_if<std::is_array<T>::value, std::unique_ptr<T, Dp>>::type
+make_unique(const size_t n) {
+ return std::unique_ptr<T, Dp>(new typename std::remove_extent<T>::type[n]());
+}
+
+// Disallows 'make_unique<T[10]>()'. (N3690 s20.9.1.4 p5)
+template<typename T, typename Dp = std::default_delete<T>, typename... Args>
+typename std::enable_if<
+ std::extent<T>::value != 0, std::unique_ptr<T, Dp>>::type
+make_unique(Args&&...) = delete;
+
+/**
+ * to_shared_ptr
+ *
+ * Convert unique_ptr to shared_ptr without specifying the template type
+ * parameter and letting the compiler deduce it.
+ *
+ * So you can write this:
+ *
+ * auto sptr = to_shared_ptr(getSomethingUnique<T>());
+ *
+ * Instead of this:
+ *
+ * auto sptr = shared_ptr<T>(getSomethingUnique<T>());
+ *
+ * Useful when `T` is long, such as:
+ *
+ * using T = foobar::cpp2::FooBarServiceAsyncClient;
+ */
+template <typename T>
+std::shared_ptr<T> to_shared_ptr(std::unique_ptr<T>&& ptr) {
+ return std::shared_ptr<T>(std::move(ptr));