Nicko van Someren wrote:
> >>> sum(['a','b','c'])
> Traceback (most recent call last):
> File "<stdin>", line 1, in <module>
> TypeError: unsupported operand type(s) for +: 'int' and 'str'
> >>> sum([["a"],[u'b'],[3]])
> Traceback (most recent call last):
> File "<stdin>", line 1, in <module>
> TypeError: unsupported operand type(s) for +: 'int' and 'list'
You can already make the second example work properly by supplying an
appropriate starting value:
>>> sum([["a"],[u'b'],[3]], [])
['a', u'b', 3]
(and a similar call will also work for the new bytes type, as well as
other sequences)
Strings are explicitly disallowed (because Guido doesn't want a second
way to spell ''.join(seq), as far as I know):
>>> sum(['a','b','c'], '')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: sum() can't sum strings [use ''.join(seq) instead]
Cheers,
Nick.
--
Nick Coghlan | [EMAIL PROTECTED] | Brisbane, Australia
---------------------------------------------------------------
http://www.boredomandlaziness.org
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