code: static Parser<Expression> simpleNewExpression(Parser<Expression> arg, Parser<DefBody> body) {
      return Parsers.sequence(
          term("new").next(TypeLiteralParser.ELEMENT_TYPE_LITERAL),
          argumentList(arg),
          body.optional(),
          (type, args, defBody) -> new NewExpression(null, type, args, defBody));
    }
docs: new a class instance