Add concatenate function.

changelog

@@ -6,6 +6,7 @@ Version 1.9.3+svn:
  * Formula language:
    * Added substring function.
    * Added length function, to determine the length of a string.
+   * Added concatenate function.
  * Graphics:
    * Terrain: added transitions for the wood floor.
  * Language and i18n:

src/formula_function.cpp

@@ -435,6 +435,27 @@ public:
 	}
 };
 
+class concatenate_function
+		: public function_expression {
+public:
+		explicit concatenate_function(const args_list& args)
+			: function_expression("concatenate", args, 1, -1)
+		{}
+
+private:
+		variant execute(const formula_callable& variables
+						, formula_debugger *fdb) const {
+
+				std::string result;
+
+				foreach(expression_ptr arg, args()) {
+						result += arg->evaluate(variables, fdb).string_cast();
+				}
+
+				return variant(result);
+		}
+};
+
 class index_of_function : public function_expression {
 public:
 	explicit index_of_function(const args_list& args)
@@ -1118,6 +1139,7 @@ functions_map& get_functions_map() {
 		FUNCTION(tomap);
 		FUNCTION(substring);
 		FUNCTION(length);
+		FUNCTION(concatenate);
 #undef FUNCTION
 	}
 

src/tests/test_formula_function.cpp

@@ -98,5 +98,28 @@ BOOST_AUTO_TEST_CASE(test_formula_function_length)
 			, 11);
 }
 
+BOOST_AUTO_TEST_CASE(test_formula_function_concatenate)
+{
+	BOOST_CHECK_EQUAL(
+			  game_logic::formula("concatenate(100)").evaluate().as_string()
+			, "100");
+
+	BOOST_CHECK_EQUAL(
+			  game_logic::formula("concatenate(100, 200, 'a')")
+				.evaluate().as_string()
+			, "100200a");
+
+	BOOST_CHECK_EQUAL(
+			  game_logic::formula("concatenate([1,2,3])")
+				.evaluate().as_string()
+			, "1, 2, 3");
+
+	BOOST_CHECK_EQUAL(
+			  game_logic::formula(
+					"concatenate([1.0, 1.00, 1.000, 1.2, 1.23, 1.234])")
+						.evaluate().as_string()
+			, "1.000, 1.000, 1.000, 1.200, 1.230, 1.234");
+}
+
 BOOST_AUTO_TEST_SUITE_END()