On 12/03/2021 11.27, Chris Angelico wrote: > On Fri, Mar 12, 2021 at 9:10 AM Ethan Furman <et...@stoneleaf.us> wrote: >> >> On 3/11/21 1:45 PM, dn via Python-list wrote: >> >>> Is assert so much faster/cheaper than try...except...raise? >> >> Infinitely faster when they are not there. ;-) >> >> Basically, you are looking at two different philosophies: >> >> - Always double check, get good error message when something fails >> >> vs >> >> - check during testing and QA, turn off double-checks for production for >> best performance possible. >> > > There are many hybrids available too though. For instance: > > if __debug__ or args.verify: > def verify(thing): > ... > raise Whatever > else: > def verify(thing): pass > > Yes, you pay the price of a function call even if you're not verifying > the full structural integrity. But that's a lot cheaper than the full > check. > > Advantage here is that you can use -O to suppress, or you can control > it with an arg, or whatever. > > If you're doing the same check in lots of places, and it's costly, > assertions aren't really a great fit.
Perhaps I misunderstood (and haven't gone back to check - mea culpa), but the impression-gained was that -O many not be used, even "in production", for some reason? Perhaps because I've not come from a language where assert played any/a major rôle, but am still hoping for some discussion/understanding as to why/when assert might be better than try...except in every/particular situations... -- Regards, =dn -- https://mail.python.org/mailman/listinfo/python-list
