Recently someone asked about the class Squeak.Color in Cincom Smalltalk in the latest development builds and was stunned to find that when they browsed to it, they ended up on Graphics.ColorValue.
What's going on here? We've aliased the Squeak.Color value to Graphics.ColorValue. The basic reason for doing this is because the two classes are effectively the same between Squeak and Cincom Smalltalk. The second reason is that Seaside extends Color with various methods. There is a great deal of trickery in the color code used by Scriptaculous and CSSBarGraphs and a few other Seaside libraries - so instead of making Squeak.Color a subclass of Graphics.ColorValue, I chose to alias it instead.
So how do you do that? Well, it turns out it's pretty easy. Click on the namespace you want to add the alias to and add a shared variable, eg: MyNamespace.MyString and sit its initializer to be the class you want it to alias to - in this case Core.String. Initialize the shared variable and you're done.
The tools are aware of this trick, so they'll work correctly, allowing you to subclass it, reference it in #{}'s, so on and so forth. Happy class aliasing!