Re: HasCallStack constraint for maximum in Prelude?

On Wed, Mar 25, 2026 at 11:56:21PM +1100, Viktor Dukhovni wrote:
> On Wed, Mar 25, 2026 at 10:23:37AM +0000, Tom Ellis wrote:
> 
> > On Wed, Mar 25, 2026 at 11:19:20AM +0100, Olaf Klinke via Haskell-Cafe wrote:
> > > For (Bounded a, Ord a) one should replace maximum by an ordinary fold,
> > > given a suitable newtype wrapper with a Monoid instance, e.g. 
> > > 
> > > (Ord a, Bounded a) => Monoid (Data.Semigroup.Max a)
> > 
> > For a Semigroup surely it doesn't need Bounded?  (A Monoid would
> > need Bounded).
> 
> What Olaf seems to have in mind does neet a Monoid, for example:

Yes, I misunderstood the type `Data.Semigroup.Max` (which just happens
to live in `Data.Semigroup`) for the `Semigroup` class. I missed that
the class is actually `Monoid`.

Tom
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