Are the critiques in "All the things I hate about Python" valid?

[Chris Angelico]

On Wed, Feb 21, 2018 at 7:42 AM, Rick Johnson
<rantingrickjohnson at gmail.com> wrote:
> On Tuesday, February 20, 2018 at 2:18:31 PM UTC-6, MRAB wrote:
>
>> The point he was making is that if you store a person's age, you'd have
>> to update it every year. It's far better to store the date of birth and
>> calculate the age on demand.
>
> *AHEM*
>
> At the risk of being labeled a "quibbler" (which, in the
> grander scheme is not really all that bad considering some
> of the names that have been attributed to me), i must say
> your advice is only "sound advice" in cases where the age
> will not be queried frequently.
>
> For instance, if the age is queried many times a second, it
> would be a much wiser design to set-up an event that will
> advance the age at the end of the last second of every year,
> instead of doing the age calculation many times a second.
> Heck, even if the frequency is multiple time a day, a valid
> argument could be made.

Nope. Even if you need the age many times per second, it's still
better to store the date of birth, because you eliminate boundary
conditions and duplicated data. But that's assuming you're storing the
age of *a person*. If the age in question is a boundary ("motor
insurance premiums are increased if the driver is 65 years or older"),
then it's still sane to store the age.

ChrisA