Re: HasCallStack constraint for maximum in Prelude?

Mathematically, the least amount of structure needed for maximum and
minimum is a bounded semilattice, which in contrast to the Bounded
class requires only one bound to exist. Such structures are defined for
example in the semilattices [1] and lattices [2] packages. 
The semilattices package provides the instances
 
(Lower a, Join a) => Monoid (Joining a)
(Upper a, Meet a) => Monoid (Meeting a)

whereas the lattices package provides the 
BoundedJoinSemilattice and BoundedMeetSemilattice classes and the
functions

joins :: (BoundedJoinSemiLattice a, Foldable f) => f a -> a
meets :: (BoundedMeetSemiLattice a, Foldable f) => f a -> a
joins1 :: (Lattice a, Foldable1 f) => f a -> a
meets1 :: (Lattice a, Foldable1 f) => f a -> a 

as well as the wrappers Meet and Join with appropriate Monoid instances
to recover the joins and meets functions via foldMap. 

Olaf

[1] https://hackage.haskell.org/package/semilattices
[2] https://hackage.haskell.org/package/lattices
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