struct::queue(n) Tcl Data Structures struct::queue(n) 







struct::queue - Create and manipulate queue objects








package require Tcl 8.4


package require struct::queue ?1.4.2?


queueName option ?arg arg ...?


queueName clear


queueName destroy


queueName get ?count?


queueName peek ?count?


queueName put item ?item ...?


queueName unget item


queueName size












The ::struct namespace contains a commands for processing
    finite queues.


It exports a single command, ::struct::queue. All
    functionality provided here can be reached through a subcommand of this
    command.


Note: As of version 1.4.1 of this package a critcl based C
    implementation is available. This implementation however requires Tcl 8.4 to
    run.


The ::struct::queue command creates a new queue object with
    an associated global Tcl command whose name is queueName. This
    command may be used to invoke various operations on the queue. It has the
    following general form:



  

  
Option and the args determine the exact behavior of the
      command. The following commands are possible for queue objects:

  

  
Remove all items from the queue.

  

  
Destroy the queue, including its storage space and associated
    command.

  

  
Return the front count items of the queue and remove them from the
      queue. 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
      not enoughs items in the queue to fulfull the request, this command will
      throw an error.

  

  
Return the front count items of the queue, without removing them
      from the queue. 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 not enoughs items in the queue to fulfull the request, this command
      will throw an error.

  

  
Put the item or items specified into the queue. If more than one
      item is given, they will be added in the order they are
    listed.

  

  
Put the item into the queue, at the front, i.e. before any other
      items already in the queue. This makes this operation the complement to
      the method get.

  

  
Return the number of items in the queue.










This document, and the package it describes, will undoubtedly
    contain bugs and other problems. Please report such in the category
    struct :: queue of the Tcllib SF Trackers
    [http://sourceforge.net/tracker/?group_id=12883]. Please also report any
    ideas for enhancements you may have for either package and/or
  documentation.








graph, list, matrix, pool, prioqueue, record, set, skiplist,
    stack, tree








Data structures







  

    1.4.2
    struct