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(** Value on which validators try to reach a consensus.

    Consensus at a given level is reached on a sequence of operations.  However,
    to differentiate between two blocks having the same sequence of operations,
    assuming that could ever happen (for instance, two empty blocks), we also
    include the hash of the block that precedes the block where these operations
    should be included. *)

let hash ~predecessor round operations_hash =
  let open Data_encoding in
  let predecessor = Binary.to_bytes_exn Block_hash.encoding predecessor in
  let round = Binary.to_bytes_exn Round_repr.encoding round in
  let operations_hash =
    Binary.to_bytes_exn Operation_list_hash.encoding operations_hash
  in
  Block_payload_hash.hash_bytes [predecessor; round; operations_hash]