, before final hash value is calculated.
Note: implementations are required to retain state so that it is possible
to calculate "partial" hash values throughout content, and call
multiple times, at different points. This is different
from many other hash calculation abstractions.
NOTE: since 0.9.21, this implements
, for interoperability
. This will NOT reset state, so it is completely legal to feed more content with
, and calculate further hash codes with same instance.
NOTE: since no state is reset with a call, calling this method typically results in calculation to finalize state. So if you need to access same hash value multiple times, call this method once and retain hash value.