Exemplo n.º 1
0
        private Stmt ForStatement()
        {
            Consume(LEFT_PAREN, "Expect '(' after 'for'.");

            Stmt initializer;

            if (Match(SEMICOLON))
            {
                initializer = null;
            }
            else if (Match(VAR))
            {
                initializer = VarDeclaration();
            }
            else
            {
                initializer = ExpressionStatement();
            }

            Expr condition = null;

            if (!Check(SEMICOLON))
            {
                condition = Expression();
            }
            Consume(SEMICOLON, "Expect ';' after loop condition.");

            Expr increment = null;

            if (!Check(RIGHT_PAREN))
            {
                increment = Expression();
            }
            Consume(RIGHT_PAREN, "Expect ')' after for clauses.");

            Stmt body = Statement();

            if (increment != null)
            {
                body = new Stmt.Block(new[] { body, new Stmt.Expression(increment) });
            }

            if (condition == null)
            {
                condition = new Expr.Literal(true);
            }
            body = new Stmt.While(condition, body);

            if (initializer != null)
            {
                body = new Stmt.Block(new[] { initializer, body });
            }

            return(body);
        }
Exemplo n.º 2
0
 public object VisitLiteralExpr(Expr.Literal expr)
 {
     return(null);
 }