moved parameter_binder from member to parameter to bind, execute and fetch methods

include/matador/sql/interface/statement_impl.hpp

@@ -3,6 +3,7 @@
 
 #include "matador/sql/query_context.hpp"
 #include "matador/sql/internal/query_result_impl.hpp"
+#include "matador/sql/interface/parameter_binder.hpp"
 #include "matador/sql/object_parameter_binder.hpp"
 
 #include "matador/utils/data_type_traits.hpp"
@@ -21,24 +22,23 @@ protected:
 public:
   virtual ~statement_impl() = default;
 
-  virtual utils::result<size_t, utils::error> execute() = 0;
-  virtual utils::result<std::unique_ptr<query_result_impl>, utils::error> fetch() = 0;
+  virtual utils::result<size_t, utils::error> execute(const interface::parameter_binder& bindings) = 0;
+  virtual utils::result<std::unique_ptr<query_result_impl>, utils::error> fetch(const interface::parameter_binder& bindings) = 0;
 
   template < class Type >
-  void bind_object(Type &obj)
-  {
+  void bind_object(Type &obj, const interface::parameter_binder& bindings) {
     object_parameter_binder object_binder_;
     object_binder_.reset(start_index());
-    object_binder_.bind(obj, binder());
+    object_binder_.bind(obj, bindings);
   }
 
   template < class Type >
-  void bind(const size_t pos, Type &val) {
-    utils::data_type_traits<Type>::bind_value(binder(), adjust_index(pos), val);
+  void bind(const size_t pos, Type &val, const interface::parameter_binder& bindings) {
+    utils::data_type_traits<Type>::bind_value(bindings, adjust_index(pos), val);
   }
 
-  void bind(size_t pos, const char *value, size_t size);
-  void bind(size_t pos, std::string &val, size_t size);
+  void bind(size_t pos, const char *value, size_t size, interface::parameter_binder& bindings) const;
+  void bind(size_t pos, std::string &val, size_t size, interface::parameter_binder& bindings) const;
 
   virtual void reset() = 0;
 
@@ -46,12 +46,13 @@ public:
   [[nodiscard]] bool is_valid_host_var(const std::string &host_var, size_t pos) const;
 
 protected:
-  virtual utils::attribute_writer& binder() = 0;
   [[nodiscard]] virtual size_t start_index() const;
   [[nodiscard]] virtual size_t adjust_index(size_t index) const;
+  [[nodiscard]] virtual std::unique_ptr<utils::attribute_writer> create_binder() const = 0;
 
 protected:
   friend class statement;
+  friend class statement_proxy;
 
   query_context query_;
 };