Well, first off, program code is not one-dimensional; you would be more correct saying that it's "two-dimensional", which is is why indentation is helpful at all. Also, saying " text is one-dimensional" is almost as superficial as saying that a book is just a stack of paper. No, it is more than that, of course, and so is text in general. When you are reading, do you imagine a one dimensional world? Of course not, and that is how text's "dimensionality" should be measured, not by its appearance as a mere sequence of markings on paper or a computer screen.