added switch statement to getenv

Author: glaukiol1

os/os.module.go

@@ -102,15 +102,16 @@ func getenv(self py.Object, args py.Tuple) (py.Object, error) {
 		dflt py.Object = py.None
 		err  error
 	)
-
-	if len(args) == 1 {
+	switch len(args) {
+	case 1:
 		if objectIsString(args[0]) {
 			key = args[0]
 		} else {
 			return nil, py.ExceptionNewf(py.TypeError, "str expected (pos 1), not "+args[0].Type().Name)
 		}
 		dflt = py.None
-	} else if len(args) == 2 {
+		break
+	case 2:
 		if objectIsString(args[0]) {
 			key = args[0]
 		} else {
@@ -122,7 +123,8 @@ func getenv(self py.Object, args py.Tuple) (py.Object, error) {
 		} else {
 			return nil, py.ExceptionNewf(py.TypeError, "str expected (pos 2), not"+args[1].Type().Name)
 		}
-	} else {
+		break
+	default:
 		return nil, py.ExceptionNewf(py.TypeError, "missing one required argument: 'name:str'")
 	}
 	var res py.Object // hold the result value