Python is faster than C

[Raymond Hettinger]

[Armin Rigo]
>     Armin> Worse, and more importantly, the optimization starts to
>     Armin> become visible to the programmer.  Iterators, for example,
>     Armin> are great in limited cases but I consider their
>     Armin> introduction a significant complication in the language;
>     Armin> before, you could expect that some function from which you
>     Armin> would expect a sequence returned a list.  Python was all
>     Armin> lists and

[Ville Vainio]
> Iterators are an optimization? I always considered them just a more
> clean and elegant way to do the same thing :-).

In the planning discussions, optimization was not mentioned as goal. 
In fact, I think everyone was surprised that they happened to run
faster than the __getitem__ hack.  It was also a surprise at how much
they unified the language and made the various pieces work together a
little better.

The original goals were much smaller:
* less cumbersome file iteration (eliminating the need for xreadlines
and reducing the need for the fileinput module).
* providing an extensible interface
* making the code for non-sequence collections more concise and
readable

There was a thought that the performance of dictionary iteration would
improve.  Also, while it was not discussed explicitly, everyone was
aware that iterators were more memory/cache friendly than their list
based counterparts.


Raymond Hettinger