compat/make-unique: add std::make_unique sample impl

It's not present in GNU with -std=c++14

1 files changed, 43 insertions, 0 deletions

diff --git a/opentrack-compat/make-unique.hpp b/opentrack-compat/make-unique.hpp
new file mode 100644
index 00000000..bb5315c5
--- /dev/null
+++ b/opentrack-compat/make-unique.hpp
@@ -0,0 +1,43 @@
+#pragma once
+
+// GNU 5.4.0 doesn't have std::make_unique in -std=c++14 mode
+
+// this implementation was taken from http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3656.htm
+
+#include <memory>
+#include <utility>
+#include <cstddef>
+
+namespace detail {
+template<class T> struct Unique_if
+{
+    typedef std::unique_ptr<T> Single_object;
+};
+
+template<class T> struct Unique_if<T[]>
+{
+    typedef std::unique_ptr<T[]> Unknown_bound;
+};
+
+template<class T, size_t N> struct Unique_if<T[N]>
+{
+    typedef void Known_bound;
+};
+}
+
+template<class T, class... Args>
+    typename detail::Unique_if<T>::Single_object
+    make_unique(Args&&... args) {
+        return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
+    }
+
+template<class T>
+    typename detail::Unique_if<T>::Unknown_bound
+    make_unique(std::size_t n) {
+        typedef typename std::remove_extent<T>::type U;
+        return std::unique_ptr<T>(new U[n]());
+    }
+
+template<class T, class... Args>
+    typename detail::Unique_if<T>::Known_bound
+    make_unique(Args&&...) = delete;