PEP 289: Generator Expressions (please comment)

[Skip Montanaro]

    Ville> However, I'm not completely sure about allowing them to be
    Ville> creatad w/o parens in function calls, seems a bit too magical for
    Ville> my taste.

Think of parens and genex's the same way you'd think of parens and tuples.
Creating tuples often doesn't require parens either, but sometimes does in
cases where the syntax would be ambiguous).  As arguments to function calls,
parens would be required to separate generator expressions from other
arguments.  In the one arg case they aren't required (though you're free to
add them if it warms the cockles of your heart ;-).

Skip