# Module type Hashtbl.HashedType

    module type HashedType = sig  end

The input signature of the functor `Hashtbl.Make`.

`type t`
The type of the hashtable keys.

    val equal : t -> t -> bool

The equality predicate used to compare keys.

    val hash : t -> int

A hashing function on keys. It must be such that if two keys are equal according to `equal`, then they have identical hash values as computed by `hash`. Examples: suitable (`equal`, `hash`) pairs for arbitrary key types include (`(=)`, `Hashtbl.hash`) for comparing objects by structure, and (`(==)`, `Hashtbl.hash`) for comparing objects by addresses (e.g. for mutable or cyclic keys).