Key (hmap.Hmap.Key)

Keys

val create : unit -> 'a key

create () is a new key.

Exisential keys allows to compare keys. This can be useful for functions like filter.

type t

The type for existential keys.

val hide_type : 'a key -> t

hide_type k is an existential key for k.

val equal : t -> t -> bool

equal k k' is true iff k and k' are the same key.

val compare : t -> t -> int

compare k k' is a total order on keys compatible with equal.