Fixed possible dangling references problem

include/sqlpp11/remove.h

@@ -116,9 +116,9 @@ namespace sqlpp
 				static Context& _(const T& t, Context& context)
 				{
 					context << "DELETE";
-					interpret(t._from, context);
+					interpret(t._from(), context);
-					interpret(t._using, context);
+					interpret(t._using(), context);
-					interpret(t._where, context);
+					interpret(t._where(), context);
 					return context;
 				}
 			};

include/sqlpp11/select.h

@@ -191,15 +191,15 @@ namespace sqlpp
 				{
 					context << "SELECT ";
 
-					interpret(t._flag_list, context);
+					interpret(t._flag_list(), context);
-					interpret(t._column_list, context);
+					interpret(t._column_list(), context);
-					interpret(t._from, context);
+					interpret(t._from(), context);
-					interpret(t._where, context);
+					interpret(t._where(), context);
-					interpret(t._group_by, context);
+					interpret(t._group_by(), context);
-					interpret(t._having, context);
+					interpret(t._having(), context);
-					interpret(t._order_by, context);
+					interpret(t._order_by(), context);
-					interpret(t._limit, context);
+					interpret(t._limit(), context);
-					interpret(t._offset, context);
+					interpret(t._offset(), context);
 
 					return context;
 				}

include/sqlpp11/vendor/from.h

@@ -72,7 +72,7 @@ namespace sqlpp
 						_dynamic_tables.emplace_back(table);
 					}
 
-				from_t& _from = *this;
+				const from_t& _from() const { return *this; }
 				std::tuple<Tables...> _tables;
 				vendor::interpretable_list_t<Database> _dynamic_tables;
 			};
@@ -80,7 +80,7 @@ namespace sqlpp
 		struct no_from_t
 		{
 			using _is_from = std::true_type;
-			no_from_t& _from = *this;
+			const no_from_t& _from() const { return *this; }
 		};
 
 		// CRTP Wrappers

include/sqlpp11/vendor/group_by.h

@@ -71,7 +71,7 @@ namespace sqlpp
 						_dynamic_expressions.emplace_back(expression);
 					}
 
-				group_by_t& _group_by = *this;
+				const group_by_t& _group_by() const { return *this; }
 				_parameter_tuple_t _expressions;
 				vendor::interpretable_list_t<Database> _dynamic_expressions;
 			};
@@ -79,7 +79,7 @@ namespace sqlpp
 		struct no_group_by_t
 		{
 			using _is_group_by = std::true_type;
-			no_group_by_t& _group_by = *this;
+			const no_group_by_t& _group_by() const { return *this; }
 		};
 
 		// CRTP Wrappers

include/sqlpp11/vendor/having.h

@@ -69,7 +69,7 @@ namespace sqlpp
 						_dynamic_expressions.emplace_back(expr);
 					}
 
-				having_t& _having = *this;
+				const having_t& _having() const { return *this; }
 				_parameter_tuple_t _expressions;
 				vendor::interpretable_list_t<Database> _dynamic_expressions;
 			};
@@ -77,7 +77,7 @@ namespace sqlpp
 		struct no_having_t
 		{
 			using _is_having = std::true_type;
-			no_having_t& _having = *this;
+			const no_having_t& _having() const { return *this; }
 		};
 
 		// CRTP Wrappers

include/sqlpp11/vendor/limit.h

@@ -52,7 +52,7 @@ namespace sqlpp
 				limit_t& operator=(limit_t&&) = default;
 				~limit_t() = default;
 
-				limit_t& _limit = *this;
+				const limit_t& _limit() const { return *this; }
 				Limit _value;
 			};
 
@@ -88,8 +88,7 @@ namespace sqlpp
 						_initialized = true;
 					}
 
-#warning this is stupid! Will get dangling references when copying
+				const dynamic_limit_t& _limit() const { return *this; }
-				dynamic_limit_t& _limit = *this;
 				
 				bool _initialized = false;
 				interpretable_t<Database> _value;
@@ -98,7 +97,7 @@ namespace sqlpp
 		struct no_limit_t
 		{
 			using _is_limit = std::true_type;
-			no_limit_t& _limit = *this;
+			const no_limit_t& _limit() const { return *this; }
 		};
 
 		// CRTP Wrappers

include/sqlpp11/vendor/offset.h

@@ -52,7 +52,7 @@ namespace sqlpp
 				offset_t& operator=(offset_t&&) = default;
 				~offset_t() = default;
 
-				offset_t& _offset = *this;
+				const offset_t& _offset() const { return *this; }
 
 				Offset _value;
 			};
@@ -89,7 +89,7 @@ namespace sqlpp
 						_initialized = true;
 					}
 
-				dynamic_offset_t& _offset = *this;
+				const dynamic_offset_t& _offset() const { return *this; }
 				bool _initialized = false;
 				interpretable_t<Database> _value;
 			};
@@ -97,7 +97,7 @@ namespace sqlpp
 		struct no_offset_t
 		{
 			using _is_offset = std::true_type;
-			no_offset_t& _offset = *this;
+			const no_offset_t& _offset() const { return *this; }
 		};
 
 		// CRTP Wrappers

include/sqlpp11/vendor/order_by.h

@@ -70,7 +70,7 @@ namespace sqlpp
 						_dynamic_expressions.push_back(expressions);
 					}
 
-				order_by_t& _order_by = *this;
+				const order_by_t& _order_by() const { return *this; }
 				_parameter_tuple_t _expressions;
 				vendor::interpretable_list_t<Database> _dynamic_expressions;
 			};
@@ -78,7 +78,7 @@ namespace sqlpp
 		struct no_order_by_t
 		{
 			using _is_order_by = std::true_type;
-			no_order_by_t& _order_by = *this;
+			const no_order_by_t& _order_by() const { return *this; }
 		};
 
 		// CRTP Wrappers

include/sqlpp11/vendor/select_column_list.h

@@ -188,7 +188,7 @@ namespace sqlpp
 						_dynamic_columns.push_back(namedExpr);
 					}
 
-				select_column_list_t& _column_list = *this;
+				const select_column_list_t& _column_list() const { return *this; }
 				_parameter_tuple_t _columns;
 				dynamic_select_column_list<Database> _dynamic_columns;
 			};
@@ -196,7 +196,7 @@ namespace sqlpp
 		struct no_select_column_list_t
 		{
 			using _is_select_column_list = std::true_type;
-			no_select_column_list_t& _column_list = *this;
+			const no_select_column_list_t& _column_list() const { return *this; }
 		};
 
 		// CRTP Wrappers

include/sqlpp11/vendor/select_flag_list.h

@@ -70,7 +70,7 @@ namespace sqlpp
 						_dynamic_flags.emplace_back(flag);
 					}
 
-				select_flag_list_t& _flag_list = *this;
+				const select_flag_list_t& _flag_list() const { return *this; }
 				_parameter_tuple_t _flags;
 				vendor::interpretable_list_t<Database> _dynamic_flags;
 			};
@@ -78,7 +78,7 @@ namespace sqlpp
 		struct no_select_flag_list_t
 		{
 			using _is_select_flag_list = std::true_type;
-			no_select_flag_list_t& _flag_list = *this;
+			const no_select_flag_list_t& _flag_list() const { return *this; }
 		};
 
 		// CRTP Wrappers

include/sqlpp11/vendor/using.h

@@ -71,14 +71,14 @@ namespace sqlpp
 						_dynamic_tables.emplace_back(table);
 					}
 
-				using_t& _using = *this;
+				const using_t& _using() const { return *this; }
 				_parameter_tuple_t _tables;
 				vendor::interpretable_list_t<Database> _dynamic_tables;
 			};
 
 		struct no_using_t
 		{
-			no_using_t& _using = *this;
+			const no_using_t& _using() const { return *this; }
 		};
 
 		// CRTP Wrapper

include/sqlpp11/vendor/where.h

@@ -71,7 +71,7 @@ namespace sqlpp
 						_dynamic_expressions.emplace_back(expr);
 					}
 
-				where_t& _where = *this;
+				const where_t& _where() const { return *this; }
 				_parameter_tuple_t _expressions;
 				vendor::interpretable_list_t<Database> _dynamic_expressions;
 			};
@@ -88,7 +88,7 @@ namespace sqlpp
 		struct no_where_t
 		{
 			using _is_where = std::true_type;
-			no_where_t& _where = *this;
+			const no_where_t& _where() const { return *this; }
 		};
 
 		// CRTP Wrappers