A mailbox is a first-in-first-out queue where the operation of removing an element blocks if the queue is empty. Mailboxes are implemented in the concurrency.mailboxes vocabulary.

mailbox

<mailbox> ( -- mailbox )

Removing the first element:

mailbox-get ( mailbox -- obj )

mailbox-get-timeout ( mailbox timeout -- obj )

Removing the first element matching a predicate:

mailbox-get? ( mailbox pred -- obj )

mailbox-get-timeout? ( mailbox timeout pred -- obj )

Emptying out a mailbox:

mailbox-get-all ( mailbox -- seq )

mailbox-get-all-timeout ( mailbox timeout -- seq )

Adding an element:

mailbox-put ( obj mailbox -- )

Testing if a mailbox is empty:

mailbox-empty? ( mailbox -- bool )

while-mailbox-empty ( mailbox quot -- )