>It's not, because there does not exist an editor that is smart enough to recognize that these 4 spaces are indentation tabs while these 4 spaces are spacing sp

>It's not, because there does not exist an editor that is smart enough to recognize that these 4 spaces are indentation tabs while these 4 spaces are spacing spaces. Oh yes I see your point. All the more reason to use tabs for indentation and spaces for alignment. :)