 [det]crypto_data_context(+Data, 
+Context0, -Context)Context0 is an existing computation context, and Context 
is the new context after hashing Data in addition to the 
previously hashed data. Context0 may be produced by a prior 
invocation of either crypto_context_new/2 
or crypto_data_context/3 
itself.
[det]crypto_data_context(+Data, 
+Context0, -Context)Context0 is an existing computation context, and Context 
is the new context after hashing Data in addition to the 
previously hashed data. Context0 may be produced by a prior 
invocation of either crypto_context_new/2 
or crypto_data_context/3 
itself.
This predicate allows a hash to be computed in chunks, which may be 
important while working with Metalink (RFC 5854), BitTorrent or similar 
technologies, or simply with big files.