Because it contains more non-significant symbols (, ), { and } that "steal" the programmers attention. But consider
def f(x, y, z) print x, y, z
to
def f(x, y, z): print x, y, z
IMHO, the colon-less variant is more readable than the one with the colon.
Except that it is quite acceptable to do the following:
def f(x, y, z,
long_func_arg_name):
long_func_arg_name(x, y, z)
def f(x, y, z, long_func_arg_name) long_func_arg_name(x, y, z)
The colons do a decent job of flagging the beginning of suites, mainly because of Python general lack of *other* punctuation (e.g. the colon would be entirely ineffective at improving readability if every line ended with a semi-colon).
Cheers, Nick. -- http://mail.python.org/mailman/listinfo/python-list
