Re: sorted?

On Mon, Dec 9, 2024 at 8:45 PM Mikael Djurfeldt <[email protected]>
wrote:

> On Mon, Dec 9, 2024 at 8:23 PM <[email protected]> wrote:
>
>>   (lambda (p1 p2) (< (car p1) (car p2)))
>>
>> Then you'd need a corresponding equal, because otherwise you
>> end up with things which are neither less nor equal nor greater,
>> i.e. the ordering isn't total, which is bad for sorting :)
>>
>
> `sort' assumes that the elements belong to a "strict total order", which
> means that the connectedness-axiom is true, which means that a = b is
> *equivalent to* not (a < b or a > b). So, we don't need equal.
>

Actually, a "total order" is sufficient for `sort', because equal is not
necessary for sorting. I should have said that if we have a "strict total
order" (as is almost always the case) is sufficient for the equivalence I
have been talking about.