Fix build on MSVC

actor-framework · Jun 25, 2015 · e793c81 · e793c81
1 parent 9f36b67
commit e793c81
Show file tree

Hide file tree

Showing 3 changed files with 32 additions and 33 deletions.
diff --git a/libcaf_core/caf/detail/type_list.hpp b/libcaf_core/caf/detail/type_list.hpp
@@ -34,7 +34,11 @@ namespace detail {
 
 /// A list of types.
 template <class... Ts>
-struct type_list { };
+struct type_list {
+  constexpr type_list() {
+    // nop
+  }
+};
 
 /// Denotes the empty list.
 using empty_type_list = type_list<>;
@@ -925,8 +929,8 @@ constexpr bool tlf_no_negative() {
   return true;
 }
 
-template <class T, class... Ts>
-constexpr bool tlf_no_negative(T x, Ts... xs) {
+template <class... Ts>
+constexpr bool tlf_no_negative(int x, Ts... xs) {
   return x < 0 ? false : tlf_no_negative(xs...);
 }
 
@@ -935,17 +939,12 @@ constexpr bool tlf_is_subset(type_list<Ts...>, List) {
   return tlf_no_negative(tlf_find<Ts>(List{})...);
 }
 
-template <class ListA, class ListB>
-constexpr bool tlf_is_subset() {
-  return tlf_is_subset(ListA{}, ListB{});
-}
-
 /// Tests whether ListA contains the same elements as ListB
 /// and vice versa. This comparison ignores element positions.
 template <class ListA, class ListB>
 struct tl_equal {
-  static constexpr bool value = tlf_is_subset<ListA, ListB>()
-                                && tlf_is_subset<ListB, ListA>();
+  static constexpr bool value = tlf_is_subset(ListA{}, ListB{})
+                                && tlf_is_subset(ListB{}, ListA{});
 };
 
 template <size_t N, class T>

diff --git a/libcaf_core/caf/typed_actor.hpp b/libcaf_core/caf/typed_actor.hpp
@@ -87,39 +87,39 @@ class typed_actor : detail::comparable<typed_actor<Sigs...>>,
   /// Identifies the base class of brokers implementing this interface.
   using broker_base = io::experimental::typed_broker<Sigs...>;
 
+  /// Stores the template parameter pack.
+  using signatures = detail::type_list<Sigs...>;
+
   typed_actor() = default;
   typed_actor(typed_actor&&) = default;
   typed_actor(const typed_actor&) = default;
   typed_actor& operator=(typed_actor&&) = default;
   typed_actor& operator=(const typed_actor&) = default;
 
-  template <class... OtherSigs,
-            class Enable =
-              typename std::enable_if<
-                detail::tlf_is_subset<detail::type_list<Sigs...>,
-                                      detail::type_list<OtherSigs...>>()
-              >::type>
-  typed_actor(const typed_actor<OtherSigs...>& other) : ptr_(other.ptr_) {
+  template <class TypedActor,
+            class Enable = typename std::enable_if<
+                             detail::tlf_is_subset(signatures{},
+                                                   typename TypedActor::signatures{})
+                           >::type>
+  typed_actor(const TypedActor& other) : ptr_(other.ptr_) {
     // nop
   }
 
-  template <class... OtherSigs,
-            class Enable =
-              typename std::enable_if<
-                detail::tlf_is_subset<detail::type_list<Sigs...>,
-                                      detail::type_list<OtherSigs...>>()
-              >::type>
-  typed_actor& operator=(const typed_actor<OtherSigs...>& other) {
+  template <class TypedActor,
+            class Enable = typename std::enable_if<
+                             detail::tlf_is_subset(signatures{},
+                                                   typename TypedActor::signatures{})
+                           >::type>
+  typed_actor& operator=(const TypedActor& other) {
     ptr_ = other.ptr_;
     return *this;
   }
 
   template <class Impl,
-            class Enable =
-              typename std::enable_if<
-                detail::tlf_is_subset<detail::type_list<Sigs...>,
-                                      typename Impl::signatures>()
-              >::type>
+            class Enable = typename std::enable_if<
+                             detail::tlf_is_subset(signatures{},
+                                                   typename Impl::signatures{})
+                           >::type>
   typed_actor(intrusive_ptr<Impl> other) : ptr_(std::move(other)) {
     // nop
   }

diff --git a/libcaf_core/test/metaprogramming.cpp b/libcaf_core/test/metaprogramming.cpp
@@ -90,9 +90,9 @@ CAF_TEST(metaprogramming) {
   /* test tlf_is_subset */ {
     using list_a = type_list<int, float, double>;
     using list_b = type_list<float, int, double, std::string>;
-    CAF_CHECK((tlf_is_subset<list_a, list_b>()));
-    CAF_CHECK(! (tlf_is_subset<list_b, list_a>()));
-    CAF_CHECK((tlf_is_subset<list_a, list_a>()));
-    CAF_CHECK((tlf_is_subset<list_b, list_b>()));
+    CAF_CHECK((tlf_is_subset(list_a{}, list_b{})));
+    CAF_CHECK(! (tlf_is_subset(list_b{}, list_a{})));
+    CAF_CHECK((tlf_is_subset(list_a{}, list_a{})));
+    CAF_CHECK((tlf_is_subset(list_b{}, list_b{})));
   }
 }