Migrate column_t::as to using operator::as

include/sqlpp11/column.h

@@ -94,6 +94,11 @@ namespace sqlpp
   {
   };
 
+  template<typename Table, typename ColumnSpec>
+  struct has_name<column_t<Table, ColumnSpec>> : std::true_type
+  {
+  };
+
   template <typename Context, typename Table, typename ColumnSpec>
   Context& serialize(const column_t<Table, ColumnSpec>&, Context& context)
   {

include/sqlpp11/enable_as.h

@@ -35,7 +35,7 @@ namespace sqlpp
   template <typename Expr>
   class enable_as
   {
-    constexpr decltype(auto) derived() const
+    constexpr auto derived() const -> const Expr&
     {
       return static_cast<const Expr&>(*this);
     }

include/sqlpp11/eval.h

@@ -43,7 +43,8 @@ namespace sqlpp
                   "Expression cannot be used in eval because it requires tables");
     using _name_type = alias::a_t::_alias_t;
     using _value_type = value_type_of_t<Expr>;
-    using _field_spec = field_spec_t<_name_type, _value_type, true>;
+#warning: Or do we expect users to provide the optional, too?
+    using _field_spec = field_spec_t<_name_type, sqlpp::compat::optional<_value_type>>;
     using type = typename _field_spec::cpp_type;
   };
 

include/sqlpp11/field_spec.h

@@ -34,14 +34,13 @@
 
 namespace sqlpp
 {
-  template <typename NameType, typename ValueType, bool CanBeNull>
+  template <typename NameType, typename ValueType>
   struct field_spec_t
   {
     using _alias_t = NameType;
 
-    using cpp_type = typename std::conditional<CanBeNull,
-                                               sqlpp::compat::optional<typename ValueType::_result_type>,
-                                               typename ValueType::_result_type>::type;
+#warning: Maybe rename result_value in result_value_type?
+    using cpp_type = result_value_t<ValueType>;
   };
 
   template <typename Left, typename Right, typename Enable = void>
@@ -52,18 +51,18 @@ namespace sqlpp
 
   template <typename LeftName,
             typename LeftValue,
-            bool LeftCanBeNull,
             typename RightName,
-            typename RightValue,
-            bool RightCanBeNull>
-  struct is_field_compatible<field_spec_t<LeftName, LeftValue, LeftCanBeNull>,
-                             field_spec_t<RightName, RightValue, RightCanBeNull>>
+            typename RightValue>
+  struct is_field_compatible<field_spec_t<LeftName, LeftValue>,
+                             field_spec_t<RightName, RightValue>>
   {
+    /* TODO reactivate
     static constexpr auto value =
         std::is_same<typename LeftName::_name_t, typename RightName::_name_t>::value and
         std::is_same<LeftValue, RightValue>::value and  // Same value type
         (LeftCanBeNull or !RightCanBeNull);  // The left hand side determines the result row and therefore must allow
                                              // NULL if the right hand side allows it
+                                             */
   };
 
   namespace detail
@@ -71,16 +70,17 @@ namespace sqlpp
     template <typename Select, typename NamedExpr>
     struct make_field_spec_impl
     {
+#warning: required_tables_of and obtaining the alias should handle optional.
       using RawNamedExpr = remove_optional_t<NamedExpr>;
-      using ValueType = value_type_of_t<RawNamedExpr>;
-      static constexpr bool _can_be_null = is_optional<ValueType>::value or is_optional<NamedExpr>::value;
       static constexpr bool _depends_on_outer_table =
           detail::make_intersect_set_t<required_tables_of<RawNamedExpr>,
                                        typename Select::_used_outer_tables>::size::value > 0;
+      using ValueType = typename std::conditional<_depends_on_outer_table,
+                                                  sqlpp::force_optional_t<value_type_of_t<NamedExpr>>,
+                                                  value_type_of_t<NamedExpr>>::type;
 
       using type = field_spec_t<typename RawNamedExpr::_alias_t,
-                                remove_optional_t<ValueType>,
-                                logic::any_t<_can_be_null, _depends_on_outer_table>::value>;
+                                ValueType>;
     };
   }  // namespace detail
 

include/sqlpp11/having.h

@@ -102,7 +102,7 @@ namespace sqlpp
     using type =
         static_combined_check_t<static_check_t<is_not_cpp_bool_t<Expression>::value, assert_having_not_cpp_bool_t>,
                                 static_check_t<is_expression_t<Expression>::value, assert_having_boolean_expression_t>,
-                                static_check_t<is_boolean_t<Expression>::value, assert_having_boolean_expression_t>>;
+                                static_check_t<is_boolean<Expression>::value, assert_having_boolean_expression_t>>;
   };
 
   template <typename Expression>

include/sqlpp11/on.h

@@ -39,7 +39,7 @@ namespace sqlpp
   struct check_on
   {
     using type = static_combined_check_t<static_check_t<is_expression_t<Expr>::value, assert_on_is_expression_t>,
-                                         static_check_t<is_boolean_t<Expr>::value, assert_on_is_boolean_expression_t>>;
+                                         static_check_t<is_boolean<Expr>::value, assert_on_is_boolean_expression_t>>;
   };
 
   template <typename Expr>

include/sqlpp11/operator/as_expression.h

@@ -71,6 +71,11 @@ namespace sqlpp
     using type = value_type_of_t<Expression>;
   };
 
+  template <typename Expression, typename AliasProvider>
+  struct has_name<as_expression<Expression, AliasProvider>> : std::true_type
+  {
+  };
+
   template <typename Context, typename Expression, typename AliasProvider>
   Context& serialize(const as_expression<Expression, AliasProvider>& t, Context& context)
   {
@@ -81,7 +86,7 @@ namespace sqlpp
   }
   template <typename Expr, typename AliasProvider>
   using check_as_args = std::enable_if_t<
-  is_expression_t<Expr>::value and not is_alias_t<Expr>::value and has_name<AliasProvider>::value
+  has_value_type<Expr>::value and not is_alias_t<Expr>::value and has_name<AliasProvider>::value
   >;
 
   template <typename Expr, typename AliasProvider, typename = check_as_args<Expr, AliasProvider>>

include/sqlpp11/type_traits.h

@@ -138,6 +138,10 @@ namespace sqlpp
   {
   };
 
+  template <typename T>
+  struct can_be_null : public is_optional<value_type_of_t<T>> {};
+
+#warning: remove this
   template <typename T>
   struct is_not_cpp_bool_t
   {
@@ -145,11 +149,11 @@ namespace sqlpp
   };
 
   //
-  struct boolean;
+  struct boolean{};
   template<>
   struct value_type_of<bool> { using type = boolean; };
 
-  struct integral;
+  struct integral{};
   template<>
   struct value_type_of<int8_t> { using type = integral; };
   template<>
@@ -159,7 +163,7 @@ namespace sqlpp
   template<>
   struct value_type_of<int64_t> { using type = integral; };
 
-  struct unsigned_integral;
+  struct unsigned_integral{};
   template<>
   struct value_type_of<uint8_t> { using type = unsigned_integral; };
   template<>
@@ -169,13 +173,13 @@ namespace sqlpp
   template<>
   struct value_type_of<uint64_t> { using type = unsigned_integral; };
 
-  struct floating_point;
+  struct floating_point{};
   template<>
   struct value_type_of<float> { using type = floating_point; };
   template<>
   struct value_type_of<double> { using type = floating_point; };
 
-  struct text;
+  struct text{};
   template <>
   struct value_type_of<char> { using type = text; };
   template <>
@@ -185,22 +189,22 @@ namespace sqlpp
   template <>
   struct value_type_of<sqlpp::compat::string_view> { using type = text; };
 
-  struct blob;
+  struct blob{};
   template <>
   struct value_type_of<std::vector<std::uint8_t>> { using type = blob; };
 
   template <>
   struct value_type_of<sqlpp::compat::span<std::uint8_t>> { using type = blob; };
 
-  struct day_point;
+  struct day_point{};
   template <>
   struct value_type_of<std::chrono::time_point<std::chrono::system_clock, sqlpp::chrono::days>> { using type = day_point; };
 
-  struct time_of_day;
+  struct time_of_day{};
   template <typename Rep, typename Period>
   struct value_type_of<std::chrono::duration<Rep, Period>> { using type = time_of_day; };
 
-  struct time_point;
+  struct time_point{};
   template <typename Period>
   struct value_type_of<std::chrono::time_point<std::chrono::system_clock, Period>> { using type = time_point; };
 
@@ -316,7 +320,45 @@ namespace sqlpp
 
 
   template<typename T>
-    struct parameter_value;
+    struct result_value {};
+
+  template<typename T>
+    struct result_value<sqlpp::compat::optional<T>>
+    {
+      using type = sqlpp::compat::optional<typename result_value<T>::type>;
+    };
+
+  template <typename T>
+    using result_value_t = typename result_value<T>::type;
+
+  template<>
+    struct result_value<blob> { using type = sqlpp::compat::span<uint8_t>; };
+
+  template<>
+    struct result_value<boolean> { using type = bool; };
+
+  template<>
+    struct result_value<integral> { using type = int64_t; };
+
+  template<>
+    struct result_value<unsigned_integral> { using type = uint64_t; };
+
+  template<>
+    struct result_value<floating_point> { using type = double; };
+
+  template<>
+    struct result_value<text> { using type = sqlpp::compat::string_view; };
+
+  template<>
+    struct result_value<day_point> { using type = std::chrono::time_point<std::chrono::system_clock, sqlpp::chrono::days>; };
+  template<>
+    struct result_value<time_of_day> { using type = std::chrono::microseconds; };
+
+  template<>
+    struct result_value<time_point> { using type = std::chrono::time_point<std::chrono::system_clock, std::chrono::microseconds>; };
+
+  template<typename T>
+    struct parameter_value {};
 
   template<typename T>
     struct parameter_value<sqlpp::compat::optional<T>>
@@ -339,6 +381,9 @@ namespace sqlpp
   template<>
     struct parameter_value<unsigned_integral> { using type = uint64_t; };
 
+  template<>
+    struct parameter_value<floating_point> { using type = floating_point; };
+
   template<>
     struct parameter_value<text> { using type = std::string; };
 
@@ -346,61 +391,10 @@ namespace sqlpp
     struct parameter_value<day_point> { using type = std::chrono::time_point<std::chrono::system_clock, sqlpp::chrono::days>; };
   template<>
     struct parameter_value<time_of_day> { using type = std::chrono::microseconds; };
+
   template<>
     struct parameter_value<time_point> { using type = std::chrono::time_point<std::chrono::system_clock, std::chrono::microseconds>; };
 
-#warning: These something_t data type classifiers should be removed
-  // data types
-  struct blob;
-  template <typename T>
-  using is_blob_t = std::is_same<value_type_of_t<T>, blob>;
-
-  template <typename T>
-  using is_boolean_t = std::is_same<value_type_of_t<T>, boolean>;
-
-  struct day_point;
-  template <typename T>
-  using is_day_point_t = std::is_same<value_type_of_t<T>, day_point>;
-
-  struct floating_point;
-  template <typename T>
-  using is_floating_point_t = std::is_same<value_type_of_t<T>, floating_point>;
-
-  struct integral;
-  template <typename T>
-  using is_integral_t = std::is_same<value_type_of_t<T>, integral>;
-
-  struct unsigned_integral;
-  template <typename T>
-  using is_unsigned_integral_t = std::is_same<value_type_of_t<T>, unsigned_integral>;
-
-  struct text;
-  template <typename T>
-  using is_text_t = std::is_same<value_type_of_t<T>, text>;
-
-  struct time_of_day;
-  template <typename T>
-  using is_time_of_day_t = std::is_same<value_type_of_t<T>, time_of_day>;
-
-  struct time_point;
-  template <typename T>
-  using is_time_point_t = std::is_same<value_type_of_t<T>, time_point>;
-
-  // joined data type
-  template <typename T>
-  using is_numeric_t =
-      logic::any_t<is_integral_t<T>::value, is_unsigned_integral_t<T>::value, is_floating_point_t<T>::value>;
-
-  template <typename T>
-  using is_numeric_not_unsigned_t =
-      logic::any_t<is_integral_t<T>::value, not is_unsigned_integral_t<T>::value, is_floating_point_t<T>::value>;
-
-  template <typename T>
-  using is_day_or_time_point_t = logic::any_t<is_day_point_t<T>::value, is_time_point_t<T>::value>;
-
-  template <typename T>
-  struct can_be_null : public is_optional<value_type_of_t<T>> {};
-
 #define SQLPP_VALUE_TRAIT_GENERATOR(name)                                                                   \
   namespace tag                                                                                             \
   {                                                                                                         \
@@ -678,11 +672,8 @@ namespace sqlpp
   template <typename T>
   using name_of = typename T::_alias_t::_name_t;
 
-  template<typename T, typename = void>
-  struct has_name : public std::false_type {};
-
   template<typename T>
-  struct has_name<T, typename T::_alias_t> : public std::true_type {};
+  struct has_name : public std::false_type {};
 
   template <typename ValueType, typename... Tags>
   struct make_traits

include/sqlpp11/where.h

@@ -121,7 +121,7 @@ namespace sqlpp
   //      assert_where_arg_is_not_cpp_bool_t>,
   //      static_check_t<logic::all_t<is_expression_t<Expressions>::value...>::value,
   //      assert_where_boolean_expressions_t>,
-  //      static_check_t<logic::all_t<is_boolean_t<Expressions>::value...>::value,
+  //      static_check_t<logic::all_t<is_boolean<Expressions>::value...>::value,
   //      assert_where_arg_is_boolean_expression_t>,
   //      static_check_t<logic::all_t<(not contains_aggregate_function_t<Expressions>::value)...>::value,
   //                     assert_where_arg_contains_no_aggregate_functions_t>>;
@@ -131,7 +131,7 @@ namespace sqlpp
     using type = static_combined_check_t<
         static_check_t<is_not_cpp_bool_t<Expression>::value, assert_where_arg_is_not_cpp_bool_t>,
         static_check_t<is_expression_t<Expression>::value, assert_where_arg_is_boolean_expression_t>,
-        static_check_t<is_boolean_t<Expression>::value, assert_where_arg_is_boolean_expression_t>,
+        static_check_t<is_boolean<Expression>::value, assert_where_arg_is_boolean_expression_t>,
         static_check_t<not contains_aggregate_function_t<Expression>::value,
                        assert_where_arg_contains_no_aggregate_functions_t>>;
   };

tests/core/types/result_row.cpp

@@ -176,6 +176,8 @@ int main()
   static_assert(std::is_same<sqlpp::value_type_of_t<decltype(assign(bar.intN, sqlpp::default_value))>, sqlpp::no_value_t>::value, "");
 
   // as expressions retain the value type of the real thing
+  static_assert(sqlpp::has_name<decltype(bar.intN)>::value, "");
+  sqlpp::as(bar.intN, bar.textN);
   static_assert(std::is_same<sqlpp::value_type_of_t<decltype(bar.intN.as(bar.textN))>, sqlpp::value_type_of_t<decltype(bar.intN)>>::value, "");
 
   // max can yield NULL if there are no results.
@@ -183,7 +185,6 @@ int main()
   static_assert(std::is_same<sqlpp::value_type_of_t<decltype(max(foo.textNnD))>, sqlpp::compat::optional<sqlpp::text>>::value, "");
   static_assert(std::is_same<sqlpp::value_type_of_t<decltype(sqlpp::max(7))>, sqlpp::compat::optional<sqlpp::integral>>::value, "");
 
-
 #if 0