String Implementation is done. Still has TODO that would make for good excercise.

git-svn-id: https://svn.tlawal.org/svn/monkey@57 f6afcba9-9ef1-4bdd-9b72-7484f5705bac

evaluator/evaluator.go

@@ -85,6 +85,9 @@ func Eval(node ast.Node, env *object.Environment) object.Object {
 			return args[0]
 		}
 		return apply_function(function, args)
+
+	case *ast.StringLiteral:
+		return &object.String{Value: node.Value }
 	}
 
 	return nil

evaluator/evaluator_test.go

@@ -237,6 +237,20 @@ func TestClosures(l_test *testing.T) {
 	test_integer_object(l_test, test_eval(input), 4)
 }
 
+func TestStringLiteral(l_test *testing.T){
+	input := `"Hello, world!"`
+
+	evaluated := test_eval(input)
+	string, ok := evaluated.(*object.String)
+	if !ok {
+		l_test.Fatalf("object is not String, got=%T (%+v)", evaluated, evaluated)
+	}
+
+	if string.Value != "Hello, world!" {
+		l_test.Errorf("String has wrong value, got=%q", string.Value)
+	}
+}
+
 // Helpers
 func test_eval(input string) object.Object {
 	l_lexer := lexer.New(input)

object/object.go

@@ -109,4 +109,4 @@ type String struct {
 }
 
 func (s *String) Type() ObjectType { return STRING_OBJECT }
-func (s *String) Inspec() string   { return s.Value }
+func (s *String) Inspect() string   { return s.Value }