The marshal method allows the hash's internal state to be serialized and unmarshaled at a later time, without having the re-write the entire stream of data that was already written to the hash. Fixes golang/go#24548 Change-Id: I82358c34181fc815f85d5d1509fb2fe0e62e40bd Reviewed-on: https://go-review.googlesource.com/103241 Reviewed-by: Filippo Valsorda <filippo@golang.org> Run-TryBot: Filippo Valsorda <filippo@golang.org>