Would allowing spaces in identifiers even introduce any ambiguity in most languages? I think the only languages I've seen where it would matter are functional languages. e.g. I think it'd be possible to write a Python program using spaces instead of underscores, and be able to unambiguously parse it with a slightly modified parser?
Since the space of valid syntax becomes so much larger, typos are more likely to result in valid but incorrect programs. Especially in dynamic interpreted languages like python.
> I think the only languages I've seen where it would matter are functional languages.
Yes, ML style function application is a problem and treating newlines as "normal" whitespace without having line separators (aka semicolons). And keywords used as infix operators, like another post reminded me of.
