Why assert is not a function?

[dn]

On 12/03/2021 11.27, Chris Angelico wrote:
> On Fri, Mar 12, 2021 at 9:10 AM Ethan Furman <ethan at 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