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+====== Request for Comments: LSB, parent::/self:: forwarding ======
+  * Version: 1.0
+  * Date: 2008-07-22
+  * Author: Etienne Kneuss <colder@php.net>
+  * Status: Implemented in PHP 5.3
+===== Introduction =====
+This RFC covers the change that occured to Late Static Bindings (LSB) prior to its first alpha release.
+==== Terms and concepts ====
+LSB works by passing the original call info to the function, used then by ''static::'' or get_called_class to get the original class name used. This information will only be useful in case a ''fallback'' occurs, which takes place when you call a static method that only exists in one of the parent classes.
+<code php>
+<?php
+  class A {
+     public static function who() {
+        return get_called_class();
+     }
+  }
+  class B extends A {
+  }
+  class C extends B {
+  }
+  echo C::who(); // C
+?>
+</code>
+Now let's say that you want to overwrite who in B, but still rely on A's who():
+<code php>
+<?php
+  class A {
+     public static function who() {
+        return get_called_class();
+     }
+  }
+  class B extends A {
+     public static function who() {
+         /* do stuff.. */
+         /* call A's who() */
+     }
+  }
+  class C extends B {
+  }
+  echo C::who(); // ??
+?>
+</code>
+Now, depending on how you call A's ''who()'' from ''B::who()'', you might get different results for the ''C::who()'' call:
+  - C, if the call was ''forwarding''
+  - A, if the call wasn't ''forwarding''.
+===== The change =====
+Previously, ''A::who()'' and ''parent::who()'' would be ''non-forwarding''. The only way to call A's who() with ''forwarding'' was to use an helper function: ''forward_static_call()''.
+With the change, a difference between ''parent::'' and ''A::'' is introduced, that is: ''parent::'' is ''forwarding'' while ''A::'' isn't. Basically, explicit calls are ''non-forwarding'', but calls using keywords are.
+Note that ''self::'' will also be made to be ''forwarding'', while ''<nameoftheclass>::'' won't.
+===== ML Discussion =====
+http://markmail.org/message/at3ypbykl6luwr6l

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