My $0.02 In general, I think we are going to get the most mileage by sticking with the TeX way of doing things by default. The nice thing is that ~ can be turned into a non-active character, and one can set other things if they want. For the record, I think that having non-breaking spaces in a plain text document is a bad idea. I mean, you have essentially invisible control characters. What could possibly go wrong? Hey, it could be worse. I've seen programs that use "magic comments."
As long as one can make other characters active instead, I see no reason to worry about this. But the point is that when I am debugging a TeX file I want: 1) To be able to use an editor of my choice and 2) To be able to see clearly what is going on. The fact that Python, for example treats whitespace as semantically meaningful and hence treats tabs and spaces as semantically different is a big strike against that language, for example, from a semantic clarity perspective despite the fact that this was ironically a decision that was made in order to support semantic clarity. TeX files are never simple plain text files, and I don't think we should pretend that they are. Best Wishes, Chris Travers -------------------------------------------------- Subscriptions, Archive, and List information, etc.: http://tug.org/mailman/listinfo/xetex