Use decltype(auto) for the other then overloads

STEllAR-GROUP · Mar 31, 2020 · 88918fd · 88918fd
1 parent 53b9684
commit 88918fd
Showing 1 changed file with 4 additions and 21 deletions.
diff --git a/hpx/lcos/future.hpp b/hpx/lcos/future.hpp
@@ -949,24 +949,15 @@ namespace hpx { namespace lcos
         using base_type::has_exception;
 
         template <typename F>
-        typename util::lazy_enable_if<
-            hpx::traits::is_invocable<F, future&&>::value,
-            hpx::traits::future_then_result<future, F>
-        >::type
-        then(F && f, error_code& ec = throws)
+        decltype(auto) then(F && f, error_code& ec = throws)
         {
             invalidate on_exit(*this);
             return base_type::then(std::move(*this),
                 std::forward<F>(f), ec);
         }
 
         template <typename T0, typename F>
-        typename util::lazy_enable_if<
-            !hpx::traits::is_invocable<T0, future&&>::value &&
-            hpx::traits::is_invocable<F, future&&>::value,
-            hpx::traits::future_then_result<future, F>
-        >::type
-        then(T0 && t0, F && f, error_code& ec = throws)
+        decltype(auto) then(T0 && t0, F && f, error_code& ec = throws)
         {
             invalidate on_exit(*this);
             return base_type::then(std::move(*this),
@@ -1249,22 +1240,14 @@ namespace hpx { namespace lcos
         using base_type::has_exception;
 
         template <typename F>
-        typename util::lazy_enable_if<
-            hpx::traits::is_invocable<F, shared_future&&>::value,
-            hpx::traits::future_then_result<shared_future, F>
-        >::type
-        then(F && f, error_code& ec = throws) const
+        decltype(auto) then(F && f, error_code& ec = throws) const
         {
             return base_type::then(shared_future(*this),
                 std::forward<F>(f), ec);
         }
 
         template <typename T0, typename F>
-        typename util::lazy_enable_if<
-            !hpx::traits::is_invocable<T0, shared_future&&>::value,
-            hpx::traits::future_then_result<shared_future, F>
-        >::type
-        then(T0 && t0, F && f, error_code& ec = throws) const
+        decltype(auto) then(T0 && t0, F && f, error_code& ec = throws) const
         {
             return base_type::then(shared_future(*this),
                 std::forward<T0>(t0), std::forward<F>(f), ec);