"Tuples are for heterogeneous data, lists are for homogeneous data."

[Jack Diederich]

On Tue, Mar 11, 2003 at 09:59:34PM -0500, Arthur wrote:
> The subject line is a Guido quote from today's dev list.
> 
> Is the point Guido making performance related, or is it something else? I
> have used lists extensively for heterogenous data, and wonder what it is I
> am losing by so doing.

I read the same thing, and was a little confused too.
He may mean tuples are meant to be typed, and lists generated.
So you end up with a cononical tuple of Foo's because you typed out a tuple
of Foo's.  Lists tend to accumulate more random members.

I don't pretend to channel Guido, that is just my guess.

There was a post (maybe in the byte-code python-dev thread?) that lists
are actually faster for access than tuples.  This is because lists are
more common so the common case is optmized.  I would assume that tuples are 
cheaper to instantiate.

-jackdied