metaprogramming: trait to detect smart-pointers

src/lib/meta/trait.hpp

@@ -319,6 +319,24 @@ namespace meta {
   
   
   
+  /** detect smart pointers */
+  template<typename X>
+  struct is_smart_ptr
+    : std::false_type
+    { };
+  
+  template<typename T>
+  struct is_smart_ptr<std::shared_ptr<T>>
+    : std::true_type
+    { };
+  
+  template <typename T, typename D>
+  struct is_smart_ptr<std::unique_ptr<T,D>>
+    : std::true_type
+    { };
+  
+  
+  
   
   
   

src/lib/meta/util.hpp

@@ -52,6 +52,15 @@ namespace std { // forward declaration for std::string...
   class basic_string;
   
   using string = basic_string<char, char_traits<char>, allocator<char>>;
+  
+  
+  // forward declarations for common smart ptrs
+  template<typename T>
+  class shared_ptr;
+  
+  template <typename T, typename D>
+  class unique_ptr;
+  
 }