list.reverse()

[Manuel M. Garcia]

On Fri, 15 Nov 2002 20:16:30 -0600, Mike Dean <klaatu at evertek.net>
wrote:
>I think I recall seeing a reasonable explanation for this earlier 
>(probably referring actually to list.sort()), but I'm wondering - what 
>was the rationale for making list.reverse() reverse a list in-place 
>rather than return a new, reversed list?  I'm sure there's a good 
>reason, but what might that be?

list.reverse() is implemented as a very efficient, very tight C loop,
because it is just swapping a bunch of pointers to internal Python
objects.  It requires much less time than having to make a copy,
especially since a Python object can have unlimited size and unlimited
levels of nesting of objects inside of objects.

Manuel