I think that's a side effect from keeping the parser simple. A lexer is always greedy, so whenever "([" is together in a file then it'd be parsed as a single token. However, there are cases where you can get the two tokens "(" and "[" next to each other. e.g:

string foo = ([string] bar) + "\n";

It'd be necessary to have a lot of extra special case rules in language.yacc to handle these without forcing users to put some space between "(" and "[".

Yes. There's another way it could be fixed, though: The parser could do an ad-hoc check for whitespace in those places when it reduces the closing ")" of a ([...]) or ({...}). But it's not really worth the bother.

There's always ways of making code unreadable. :)