1: <?php
 2: /**
 3:  * A binder object for binding an interface to a closure.
 4:  *
 5:  * An interface may be bound to a closure.  That closure must accept a
 6:  * Horde_Injector and return an object that satisfies the instance
 7:  * requirement. For example:
 8:  *
 9:  * <pre>
10:  * $injector->bindClosure('database', function($injector) { return new my_mysql(); });
11:  * </pre>
12:  *
13:  * @author   Bob Mckee <bmckee@bywires.com>
14:  * @author   James Pepin <james@jamespepin.com>
15:  * @author   Chuck Hagenbuch <chuck@horde.org>
16:  * @category Horde
17:  * @package  Injector
18:  */
19: class Horde_Injector_Binder_Closure implements Horde_Injector_Binder
20: {
21:     /**
22:      * TODO
23:      *
24:      * @var Horde_Injector_Binder_Closure
25:      */
26:     private $_closure;
27: 
28:     /**
29:      * Create a new Horde_Injector_Binder_Closure instance.
30:      *
31:      * @param string $closure  The closure to use for creating objects.
32:      */
33:     public function __construct($closure)
34:     {
35:         $this->_closure = $closure;
36:     }
37: 
38:     /**
39:      * TODO
40:      *
41:      * @param Horde_Injector_Binder $otherBinder  TODO
42:      *
43:      * @return boolean  Equality.
44:      */
45:     public function equals(Horde_Injector_Binder $otherBinder)
46:     {
47:         return (($otherBinder instanceof Horde_Injector_Binder_Closure) &&
48:                 ($otherBinder->getClosure() == $this->_closure));
49:     }
50: 
51:     /**
52:      * Get the closure that this binder was bound to.
53:      *
54:      * @return callable  The closure this binder is bound to.
55:      */
56:     public function getClosure()
57:     {
58:         return $this->_closure;
59:     }
60: 
61:     /**
62:      * Create instance using a closure
63:      *
64:      * If the closure depends on a Horde_Injector we want to limit its scope
65:      * so it cannot change anything that effects any higher-level scope.  A
66:      * closure should not have the responsibility of making a higher-level
67:      * scope change.
68:      * To enforce this we create a new child Horde_Injector.  When a
69:      * Horde_Injector is requested from a Horde_Injector it will return
70:      * itself. This means that the closure will only ever be able to work on
71:      * the child Horde_Injector we give it now.
72:      *
73:      * @param Horde_Injector $injector  Injector object.
74:      *
75:      * @return TODO
76:      */
77:     public function create(Horde_Injector $injector)
78:     {
79:         $childInjector = $injector->createChildInjector();
80:         $closure = $this->_closure;
81: 
82:         return $closure($childInjector);
83:     }
84: 
85: }
86: