Objects can be created by calls of the form new("queue", ...) or
by calling createQ. Existing queues can be initialized with
initQ.
Slots
queue:
Object of class "filehashDB1"
name:
Object of class "character": the name of
the queue (default is the file name in which the queue data are
stored)
Methods
isEmpty
signature(db = "queue"): returns
TRUE/FALSE depending on whether there are elements
in the queue.
pop
signature(db = "queue"): returns the value of the
"top" (i.e. head) of the queue and subsequently removes that
element from the queue; an error is signaled if the queue is empty
push
signature(db = "queue"): adds an element to the
tail ("bottom") of the queue
show
signature(object = "queue"): prints the name of
the queue
top
signature(db = "queue"): returns the value of the
"top" (i.e. head) of the queue; an error is signaled if the queue
is empty