Vocabulary
checksums.multi

Class description
This class represents the current state of a multi-checksum checksum calculation. It has an array of associated checksum states until it is disposed. You may call add-checksum-bytes multiple times to pipe data to all the checksum states in the states slot. When finished, call get-checksum to receive the results and release implementation-specific resources, or dispose to release the resources and discard the result. After the first get-checksum call the returned value is stored in the results slot, and subsequent calls return the same value.

Notes
It is not possible to add more data to the checksum after the first get-checksum call.

Most code should use with-checksum-state to make sure the resources are properly disposed of. Higher level words like checksum-bytes and checksum-stream use it to perform the disposal.

See also
multi-checksum

Definition

USING: destructors ;

IN: checksums.multi

TUPLE: multi-state < disposable states results ;

Methods

USING: accessors checksums checksums.multi kernel sequences ;

M: multi-state add-checksum-bytes
[ add-checksum-bytes ] curry [ map! ] curry change-states ;

USING: accessors checksums.multi destructors ;

M: multi-state dispose* states>> dispose-each ;

USING: accessors checksums checksums.multi kernel sequences ;

M: multi-state get-checksum
dup results>>
[ dup states>> [ get-checksum ] map [ >>results ] keep ]
unless* nip ;