@ -21,7 +21,11 @@
# define REQUIRES(...) typename enable_if<__VA_ARGS__::value, bool>::type = false
# if defined __clang__
# if (__clang_major__ >= 3)
# define OPTIONAL_HAS_USING 1
# else
# define OPTIONAL_HAS_USING 0
# endif
# if (__clang_major__ > 2) || (__clang_major__ == 2) && (__clang_minor__ >= 9)
# define OPTIONAL_HAS_THIS_RVALUE_REFS 1