proxy for the contents of a file in the file-system
include sig ... endval sexp_of_t : t ‑> Base.Sexp.tval hash_fold_t : Base.Hash.state ‑> t ‑> Base.Hash.stateval hash : t ‑> Base.Hash.hash_valueval intern : Core.Md5.t ‑> tmodule With_store : sig ... end