struct::prioqueue(3tcl) Tcl Data Structures struct::prioqueue(3tcl)______________________________________________________________________________NAME
struct::prioqueue - Create and manipulate prioqueue objects
SYNOPSIS
package require Tcl 8.2
package require struct::prioqueue ?1.4?
::struct::prioqueue ?-ascii|-dictionary|-integer|-real? ?prioqueueName?
prioqueueName option ?arg arg ...?
prioqueueName clear
prioqueueName remove item
prioqueueName destroy
prioqueueName get ?count?
prioqueueName peek ?count?
prioqueueName peekpriority ?count?
prioqueueName put item prio ?item prio ...?
prioqueueName size
_________________________________________________________________DESCRIPTION
This package implements a simple priority queue using nested tcl lists.
The command ::struct::prioqueue creates a new priority queue with
default priority key type -integer. This means that keys given to the
put subcommand must have this type.
This also sets the priority ordering. For key types -ascii and -dictio‐
nary the data is sorted in ascending order (as with lsort -increasing),
thereas for -integer and -real the data is sorted in descending order
(as with lsort -decreasing).
Prioqueue names are unrestricted, but may be recognized as options if
no priority type is given.
::struct::prioqueue ?-ascii|-dictionary|-integer|-real? ?prioqueueName?
The ::struct::prioqueue command creates a new prioqueue object
with an associated global Tcl command whose name is prioqueue‐
Name. This command may be used to invoke various operations on
the prioqueue. It has the following general form:
prioqueueName option ?arg arg ...?
option and the args determine the exact behavior of the command.
The following commands are possible for prioqueue objects:
prioqueueName clear
Remove all items from the prioqueue.
prioqueueName remove item
Remove the selected item from this priority queue.
prioqueueName destroy
Destroy the prioqueue, including its storage space and associ‐
ated command.
prioqueueName get ?count?
Return the front count items of the prioqueue (but not their
priorities) and remove them from the prioqueue. If count is not
specified, it defaults to 1. If count is 1, the result is a
simple string; otherwise, it is a list. If specified, count
must be greater than or equal to 1. If there are no or too few
items in the prioqueue, this command will throw an error.
prioqueueName peek ?count?
Return the front count items of the prioqueue (but not their
priorities), without removing them from the prioqueue. If count
is not specified, it defaults to 1. If count is 1, the result
is a simple string; otherwise, it is a list. If specified,
count must be greater than or equal to 1. If there are no or
too few items in the queue, this command will throw an error.
prioqueueName peekpriority ?count?
Return the front count items priority keys, without removing
them from the prioqueue. If count is not specified, it defaults
to 1. If count is 1, the result is a simple string; otherwise,
it is a list. If specified, count must be greater than or equal
to 1. If there are no or too few items in the queue, this com‐
mand will throw an error.
prioqueueName put item prio ?item prio ...?
Put the item or items specified into the prioqueue. prio must be
a valid priority key for this type of prioqueue, otherwise an
error is thrown and no item is added. Items are inserted at
their priority ranking. Items with equal priority are added in
the order they were added.
prioqueueName size
Return the number of items in the prioqueue.
BUGS, IDEAS, FEEDBACK
This document, and the package it describes, will undoubtedly contain
bugs and other problems. Please report such in the category struct ::
prioqueue of the Tcllib SF Trackers [http://source‐
forge.net/tracker/?group_id=12883]. Please also report any ideas for
enhancements you may have for either package and/or documentation.
KEYWORDS
ordered list, prioqueue, priority queue
CATEGORY
Data structures
COPYRIGHT
Copyright (c) 2003 Michael Schlenker <mic42@users.sourceforge.net>
struct 1.4 struct::prioqueue(3tcl)
