v01

thirdparty/Pangolin/include/pangolin/compat/optional.h

@@ -0,0 +1,20 @@
+#pragma once
+
+#include <pangolin/platform.h>
+
+// Use either C++17 optional, or the standalone backwards compatible version
+#if (__cplusplus >= 201703L)
+#   include <optional>
+#else
+#   include <experimental/optional.hpp>
+#endif
+
+namespace pangolin {
+#if (__cplusplus >= 201703L)
+template <typename T>
+using optional = std::optional<T>;
+#else
+template <typename T>
+using optional = std::experimental::optional<T>;
+#endif
+}