It's funny you mention Perl. I assume you meant Perl 5. I have toke.c open right here. You might find the *SPACE macros illuminating. They're used in functions to disambiguate lexing of, for example, unary functions, non-predeclared barewords, line number detection, unary operators (a comment there gives an example of rand +5), version numbers, method calls, use invocations, shebang line parsing, line number detection in string eval constructs, the unary minus operator, the various occurrences of the > token, and I'm only a third of the way through the file.
Can you be more specific than "I don't like Python's indentation, therefore any language with whitespace rules sucks?"