include CONTENT_ADDRESSABLE_STORE with type key = N.key
The type for content-addressable backend stores. The 'a phantom type carries information about the store mutability.
type key = N.keyThe type for keys.
find t k is Some v if k is associated to v in t and None is k is not present in t.
Write the contents of a value to the store. It's the responsibility of the content-addressable store to generate a consistent key.