To implement the tests, we need two different elt values small < big, to be able to compare those values, and to be able to construct a t containing those values.
elt
small < big
t
type t
type elt
val compare : elt ‑> elt ‑> Base.int
val small : elt
val big : elt
val of_array : elt Base.array ‑> t