Dirk Eddelbuettel <edd@debian.org> with contributions 
 by Antoine Lucas, Jarek Tuszynski, Henrik Bengtsson, Simon Urbanek,
 Mario Frasca, Bryan Lewis, Murray Stokely, Hannes Muehleisen,
 Duncan Murdoch, Jim Hester, Wush Wu, Qiang Kou, Thierry Onkelinx, 
 Michel Lang, Viliam Simko, Kurt Hornik, Radford Neal, Kendon Bell,
 Matthew de Queljoe, Ion Suruceanu, Bill Denney, Dirk Schumacher,
 and Winston Chang.
Create Compact Hash Digests of R Objects
Implementation of a function 'digest()' for the creation of hash
 digests of arbitrary R objects (using the 'md5', 'sha-1', 'sha-256', 'crc32',
 'xxhash', 'murmurhash', 'spookyhash' and 'blake3' algorithms) permitting easy
 comparison of R language objects, as well as functions such as'hmac()' to
 create hash-based message authentication code. Please note that this package
 is not meant to be deployed for cryptographic purposes for which more
 comprehensive (and widely tested) libraries such as 'OpenSSL' should be
 used.