* Steven D'Aprano:
On Sun, 28 Mar 2010 18:56:26 +0200, Alf P. Steinbach wrote:

From a more practical point of view, the sum efficiency could be
improved by doing the first addition using '+' and the rest using '+=',
without changing the behavior.

But that would change the behaviour. The __iadd__ method is not the same as the __add__ method, and you can't guarantee that they will behave the same -- or even similarly.

Hm, I don't think it's documented (except if the reference implementation serves as documentation) which one is currently used.


And what about tuples? And subclasses of list/tuples? How many different types need to be optimized?

Point. One would need to check for availability of '+='.


In practical terms, does anyone actually ever use sum on more than a handful of lists? I don't believe this is more than a hypothetical problem.

Agreed.


Cheers,

- Alf
--
http://mail.python.org/mailman/listinfo/python-list

Reply via email to