Add missing variadic template emulation in use_future.

inetic · Dec 3, 2017 · 4ad7a39 · 4ad7a39
1 parent 5c591a4
commit 4ad7a39
Showing 1 changed file with 28 additions and 0 deletions.
diff --git a/asio/include/asio/impl/use_future.hpp b/asio/include/asio/impl/use_future.hpp
@@ -543,6 +543,8 @@ template <typename Arg>
 class promise_handler_selector<void(std::exception_ptr, Arg)>
   : public promise_handler_ex_1<Arg> {};
 
+#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
+
 template <typename... Arg>
 class promise_handler_selector<void(Arg...)>
   : public promise_handler_n<std::tuple<Arg...> > {};
@@ -555,6 +557,32 @@ template <typename... Arg>
 class promise_handler_selector<void(std::exception_ptr, Arg...)>
   : public promise_handler_ex_n<std::tuple<Arg...> > {};
 
+#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
+
+#define ASIO_PRIVATE_PROMISE_SELECTOR_DEF(n) \
+  template <typename Arg, ASIO_VARIADIC_TPARAMS(n)> \
+  class promise_handler_selector< \
+    void(Arg, ASIO_VARIADIC_TARGS(n))> \
+      : public promise_handler_n< \
+        std::tuple<Arg, ASIO_VARIADIC_TARGS(n)> > {}; \
+  \
+  template <typename Arg, ASIO_VARIADIC_TPARAMS(n)> \
+  class promise_handler_selector< \
+    void(asio::error_code, Arg, ASIO_VARIADIC_TARGS(n))> \
+      : public promise_handler_ec_n< \
+        std::tuple<Arg, ASIO_VARIADIC_TARGS(n)> > {}; \
+  \
+  template <typename Arg, ASIO_VARIADIC_TPARAMS(n)> \
+  class promise_handler_selector< \
+    void(std::exception_ptr, Arg, ASIO_VARIADIC_TARGS(n))> \
+      : public promise_handler_ex_n< \
+        std::tuple<Arg, ASIO_VARIADIC_TARGS(n)> > {}; \
+  /**/
+  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_PROMISE_SELECTOR_DEF)
+#undef ASIO_PRIVATE_PROMISE_SELECTOR_DEF
+
+#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
+
 // Completion handlers produced from the use_future completion token, when not
 // using use_future::operator().
 template <typename Signature, typename Allocator>