Short-circuit all_of/any_of/none_of instantiations

STEllAR-GROUP · Aug 8, 2017 · b472866 · b472866
1 parent c721a35
commit b472866
Showing 1 changed file with 28 additions and 4 deletions.
diff --git a/hpx/util/detail/pack.hpp b/hpx/util/detail/pack.hpp
@@ -70,9 +70,16 @@ namespace hpx { namespace util { namespace detail
         >
     {};
 
+    template <typename ...Ts>
+    static std::false_type _all_of(...);
+
+    template <typename ...Ts>
+    static auto _all_of(int) -> all_of<pack_c<bool,
+        typename std::enable_if<((bool)Ts::value), bool>::type(true)...>>;
+
     template <typename ...Ts>
     struct all_of
-      : all_of<pack_c<bool, ((bool)Ts::value)...> >
+      : decltype(detail::_all_of<Ts...>(0))
     {};
 
     template <>
@@ -86,13 +93,23 @@ namespace hpx { namespace util { namespace detail
     template <bool ...Vs>
     struct any_of<pack_c<bool, Vs...> >
       : std::integral_constant<bool,
-            !all_of<pack_c<bool, !Vs...> >::value
+            !std::is_same<
+                pack_c<bool, Vs...>
+              , pack_c<bool, (Vs && false)...> // false...
+            >::value
         >
     {};
 
+    template <typename ...Ts>
+    static std::true_type _any_of(...);
+
+    template <typename ...Ts>
+    static auto _any_of(int) -> any_of<pack_c<bool,
+        typename std::enable_if<!((bool)Ts::value), bool>::type(false)...>>;
+
     template <typename ...Ts>
     struct any_of
-      : any_of<pack_c<bool, ((bool)Ts::value)...> >
+      : decltype(detail::_any_of<Ts...>(0))
     {};
 
     template <>
@@ -108,9 +125,16 @@ namespace hpx { namespace util { namespace detail
       : all_of<pack_c<bool, !Vs...> >
     {};
 
+    template <typename ...Ts>
+    static std::true_type _none_of(...);
+
+    template <typename ...Ts>
+    static auto _none_of(int) -> none_of<pack_c<bool,
+        typename std::enable_if<!((bool)Ts::value), bool>::type(true)...>>;
+
     template <typename ...Ts>
     struct none_of
-      : none_of<pack_c<bool, ((bool)Ts::value)...> >
+      : decltype(detail::_none_of<Ts...>(0))
     {};
 
     template <>