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From: Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups: comp.programming
Subject: Re: A little puzzle.
Date: Tue, 29 Nov 2022 17:37:35 +0000
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"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:

> On 2022-11-29 16:03, Richard Harnden wrote:
>
>> Okay, so how about this ... ?
>> int in_subrange(int_fast64_t range_min, int_fast64_t range_max, 
>> int_fast64_t start, int_fast64_t end, int_fast64_t check)
>> {
>>      while ( check < range_min )
>>          check += range_max - range_min;
>
> Ring modulo would be range_max - range_min + 1
>
>> It's okay for check to have 'clocked', range_min, range_max, start
>> and end have sensible values.
>
> If the language supports modular and ranged types there is no need to
> check/normalize arguments.

Part of the specification was that the inputs were intended to be valid,
though maybe that was not very clear.  In the case where this cropped
up, everything was in minutes coming from internal clocks and calendars
where the result were already in the 0-59 range.

In my view, if you need to check the arguments, that's a separate
function because what to do with bad data is so often
application-specific.  Just normalising and carrying on is only one
strategy, and one that can delay detecting bugs.  In your solution, you
normalised the degrees, minutes and seconds into a longitude beforehand,
which is all that was needed in that example.

-- 
Ben.