The Trunk: Kernel-ar.384.mcz

Andreas Raab uploaded a new version of Kernel to project The Trunk:
http://source.squeak.org/trunk/Kernel-ar.384.mcz

==================== Summary ====================

Name: Kernel-ar.384
Author: ar
Time: 1 February 2010, 8:22:34.594 pm
UUID: 312bc627-1351-5943-a531-7f75e003e29b
Ancestors: Kernel-tfel.383

Sets with nil: Merge code from http://bugs.squeak.org/view.php?id=7413 before it rots even more.

=============== Diff against Kernel-tfel.383 ===============

Item was added:
+ ----- Method: UndefinedObject>>asSetElement (in category 'sets support') -----
+ asSetElement
+ "Since nil is a singleton, we need only a single wrapper instance to represent it in set,
+ created in advance"
+ ^ SetElement withNil!

Item was added:
+ ----- Method: Object>>enclosedSetElement (in category 'accessing') -----
+ enclosedSetElement
+ "The receiver is included into a set as an element.
+ Since some objects require wrappers (see SetElement) to be able to be included into a Set,
+ a set sends this message to its element to make sure it getting real object,
+ instead of its wrapper.
+ Only SetElement instance or its subclasses allowed to answer something different than receiver itself"
+
+ !

Item was added:
+ ----- Method: Object>>asSetElement (in category 'converting') -----
+ asSetElement
+ "Answer an object, which can be put into a Set as element , wrapped
+ by one of SetElement instance, if necessary.
+ Default implementation is to answer self"
+ !