1: <?php
 2: 
 3: /**
 4:  * Jyxo PHP Library
 5:  *
 6:  * LICENSE
 7:  *
 8:  * This source file is subject to the new BSD license that is bundled
 9:  * with this package in the file license.txt.
10:  * It is also available through the world-wide-web at this URL:
11:  * https://github.com/jyxo/php/blob/master/license.txt
12:  */
13: 
14: /**
15:  * Utilities for working with arrays.
16:  *
17:  * @category Jyxo
18:  * @package Jyxo_Spl
19:  * @copyright Copyright (c) 2005-2011 Jyxo, s.r.o.
20:  * @license https://github.com/jyxo/php/blob/master/license.txt
21:  * @author Jakub Tománek
22:  */
23: class Jyxo_Spl_ArrayUtil
24: {
25:     /**
26:      * Creates an array containing item range. Similar to range() but with closures.
27:      * Params $low and $high are inclusive. If $low > $high, resulting array will be in descending order.
28:      *
29:      * @param mixed $low Minimal value
30:      * @param mixed $high Maximal value
31:      * @param Closure $step Closure which creates next value from current
32:      * @param Closure $compare comparing closure for detecting if we're at the end of the range (Optional)
33:      * @return array
34:      */
35:     public static function range($low, $high, Closure $step, Closure $compare = null)
36:     {
37:         $data = array($low);
38:         $stepDown = $low > $high;
39:         $compare = $compare ?: function ($a, $b) use ($stepDown) {
40:             return $stepDown ? $a > $b : $a < $b;
41:         };
42: 
43:         $current = $low;
44:         while ($compare($current, $high)) {
45:             $data[] = $current = $step($current);
46:         }
47:         return $data;
48:     }
49: 
50:     /**
51:      * Creates an associative array from iterator which doesn't return proper keys.
52:      * Keys are generated by applying callback $key to the current value.
53:      * It is also possible to apply another callback directly to the value.
54:      * Key callback is called BEFORE value callback.
55:      *
56:      * Example:
57:      * <code>
58:      * $data = Jyxo_Spl_ArrayUtil::keymap($iterator, function(Object $object) {
59:      *   return $object->getId();
60:      * });
61:      * </code>
62:      *
63:      * @param Traversable $traversable Iterator
64:      * @param Closure $key Closure for generating keys
65:      * @param Closure $value Closure for modifying data (Optional)
66:      * @return array
67:      */
68:     public static function keymap(Traversable $traversable, Closure $key, Closure $value = null)
69:     {
70:         $data = array();
71:         foreach ($traversable as $item) {
72:             $data[$key($item)] = $value ? $value($item) : $item;
73:         }
74:         return $data;
75:     }
76: }
77: