In a message of Mon, 29 Jun 2015 21:40:38 +0200, Ozan Çağlayan writes:

Hi,

Yes I thought of the evident question and I think I can avoid keeping everything in memory by doing two passes of the file.

Regarding __slots__, it seemed to help using CPython but pypy + slots crashed/trashed in a very hardcore way :)

PyPy always compacts instances as if they had slots, so it should make no difference. If using it makes things crash, then we have a really horrible bug -- can you post the smallest code that provokes this? (Though my bet is that you have somehting else wrong, not the slots ...) Laura