1 /*

     2 Copyright (c) 2009, Yahoo! Inc. All rights reserved.

     3 Code licensed under the BSD License:

     4 http://developer.yahoo.net/yui/license.txt

     5 version: 3.0.0b1

     6 build: 1163

     7 */

     8 YUI.add('queue-base', function(Y) {

     9 

    10 /**

    11  * <p>The Queue module adds a common data structure for FIFO operations. In its

    12  * simplest form, it is little more than an array wrapper. Additional

    13  * submodules introduce more functionality such as promotion and removal of

    14  * queued items.</p>

    15  *

    16  * <p>An AsyncQueue class is provided in the queue-run submodule.  This class

    17  * affords a mechanism to do complex sequential and iterative callback

    18  * execution across configured timeouts.

    19  *

    20  * @module queue

    21  */

    22 

    23 /**

    24  * A simple FIFO queue.  Items are added to the Queue with add(1..n items) and

    25  * removed using next().

    26  *

    27  * @module queue

    28  * @submodule queue-base

    29  * @class Queue

    30  * @param item* {MIXED} 0..n items to seed the queue

    31  */

    32 function Queue() {

    33     this._init();

    34     this.add.apply(this, arguments);

    35 }

    36 

    37 Queue.prototype = {

    38     /**

    39      * Initialize the queue

    40      *

    41      * @method _init

    42      * @protected

    43      */

    44     _init : function () {

    45         /**

    46          * The collection of enqueued items

    47          *

    48          * @property _q

    49          * @type {Array}

    50          * @protected

    51          */

    52         this._q = [];

    53     },

    54 

    55     /**

    56      * Get the next item in the queue.

    57      *

    58      * @method next

    59      * @return {MIXED} the next item in the queue

    60      */

    61     next : function () {

    62         return this._q.shift();

    63     },

    64 

    65     /**

    66      * Add 0..n items to the end of the queue

    67      *

    68      * @method add

    69      * @param item* {MIXED} 0..n items

    70      */

    71     add : function () {

    72         Y.Array.each(Y.Array(arguments,0,true),function (fn) {

    73             this._q.push(fn);

    74         },this);

    75 

    76         return this;

    77     },

    78 

    79     /**

    80      * Returns the current number of queued items

    81      *

    82      * @method size

    83      * @return {Number}

    84      */

    85     size : function () {

    86         return this._q.length;

    87     }

    88 };

    89 

    90 Y.Queue = Queue;

    91 

    92 

    93 }, '3.0.0b1' );