module Digest: sig  end
   This module provides functions to compute 128-bit ``digests'' of
   arbitrary-length strings or files. The digests are of cryptographic
   quality: it is very hard, given a digest, to forge a string having
   that digest. The algorithm used is MD5.
type t = string 
val string : string -> tval substring : string -> int -> int -> tDigest.substring s ofs len returns the digest of the substring
   of s starting at character number ofs and containing len
   characters.val channel : Pervasives.in_channel -> int -> tlen is nonnegative, Digest.channel ic len reads len
   characters from channel ic and returns their digest, or raises
   End_of_file if end-of-file is reached before len characters
   are read.  If len is negative, Digest.channel ic len reads
   all characters from ic until end-of-file is reached and return
   their digest.val file : string -> tval output : Pervasives.out_channel -> t -> unitval input : Pervasives.in_channel -> tval to_hex : t -> string