[Python-Dev] cmp(x,x) (original) (raw)

Armin Rigo arigo at tunes.org
Fri May 21 11:23:49 EDT 2004

Hello Michael,

On Fri, May 21, 2004 at 08:07:53AM -0700, Michael Chermside wrote:

Performance is certainly a legitimate concern.

Ok, then the current situation looks like the best one. I suggest we just drop a note in the documentation saying that if there are objects for which x.eq(x) isn't necessarily true, you shouldn't expect them to be handled in a fully consistent way.

But wouldn't your performance problems be fixed just as well if the tuple class implemented "identical-objects-are-immediately-equal" instead of putting it in the general comparison logic for all objects? Because if I understand correctly, that's what Armin is suggesting. Tuples would still be compared just as rapidly.

There is an extra costly indirection until the execution reaches that point.

Armin

More information about the Python-Dev mailing list