Nice.
Thanks again 
One last question…
Will you (someday) implement the ability to apply text attributes (font & color) to specific text selections ?
This would be very useful for implementing efficient custom text editors with syntax highlighting.
From what I gathered, currently, the only way for a TextEditor client to selectively apply new attributes to an existing text chunk is to re-insert the whole text while replaying the formatting commands (and thus losing the previous undo history).
Oh, and while I’m at it… I noticed that the SHIFT-DEL keypress is bound to the cut command, but its buddies CTRL-INSERT (copy) and SHIFT-INSERT (paste) aren’t…
Anyway, it’s not too important, since it can be added in subclasses.