>>>>> Hendrik van Rooyen <hend...@microcorp.co.za> (HvR) wrote:

>HvR> On Monday 20 July 2009 21:26:07 Phillip B Oldham wrote:
>>> On Jul 20, 6:08 pm, Duncan Booth <duncan.bo...@invalid.invalid> wrote:
>>> > The main reason why you need both lists and tuples is that because a
>>> > tuple of immutable objects is itself immutable you can use it as a
>>> > dictionary key.
>>> 
>>> Really? That sounds interesting, although I can't think of any real-
>>> world cases where you'd use something like that.

>HvR> simplest is something like a point in the cartesian plane with
>HvR> an associated attribute like colour.

There are numerous other examples. Anytime you need a key that is not a
single object but composed of more than one:
Name + birthday
Street + number + City
Student + Course
etc.
-- 
Piet van Oostrum <p...@cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: p...@vanoostrum.org
-- 
http://mail.python.org/mailman/listinfo/python-list

Reply via email to