introduced field_attributes shortcuts and added method on_base() to all processor classes

include/matador/sql/internal/identifier_reader.hpp

@@ -22,6 +22,8 @@ public:
     return identifier_;
   }
 
+  template<typename BaseType>
+  static void on_base(const BaseType&) {}
   template<typename ValueType>
   void on_primary_key(const char *id, ValueType &value, const utils::primary_key_attribute& attr) {
     utils::data_type_traits<ValueType>::read_value(reader_, id, column_index_, value, attr.size());

include/matador/sql/internal/object_result_binder.hpp

@@ -27,6 +27,8 @@ public:
     binder_ = nullptr;
   }
 
+  template<typename BaseType>
+  static void on_base(const BaseType&) {}
   template<typename ValueType>
   void on_primary_key(const char *id, ValueType &value, const utils::primary_key_attribute& attr);
   static void on_revision(const char * /*id*/, uint64_t &/*rev*/) {}
@@ -73,6 +75,8 @@ public:
 
   void reset();
 
+  template<typename BaseType>
+  static void on_base(const BaseType&) {}
   template < class Type >
   void on_primary_key(const char *id, Type &val, const utils::primary_key_attribute& attr) {
     utils::data_type_traits<Type>::read_value(*binder_, id, index_++, val, attr.size());

include/matador/sql/internal/pk_reader.hpp

@@ -14,6 +14,8 @@ public:
     access::process(*this, obj);
   }
 
+  template<typename BaseType>
+  static void on_base(const BaseType&) {}
   template<typename ValueType>
   void on_primary_key(const char *id, ValueType &value, const utils::primary_key_attribute& attr);
   void on_revision(const char * /*id*/, uint64_t &/*rev*/) {

include/matador/sql/internal/query_result_impl.hpp

@@ -40,6 +40,8 @@ public:
                     const std::type_index& result_type,
                     size_t column_index = 0);
 
+  template<typename BaseType>
+  static void on_base(const BaseType&) {}
   template<typename ValueType>
   void on_primary_key(const char *id, ValueType &value, const utils::primary_key_attribute& attr) {
     utils::data_type_traits<ValueType>::read_value(*reader_, id, column_index_++, value, attr.size());

include/matador/sql/internal/query_result_pk_resolver.hpp

@@ -27,6 +27,8 @@ public:
         return pk_;
     }
 
+    template<typename BaseType>
+    static void on_base(const BaseType&) {}
     template<typename ValueType>
     void on_primary_key(const char *id, ValueType &/*value*/, const utils::primary_key_attribute& attr) {
         if (!type_stack_.empty()) {