A customisable Text Editor

This should already be available but where? Should be do-able with simple scripting language?

The idea is to provide a basic text editor with some features like yours, but all features can be broken down to a script and so be modified. Also new features can be added by scripts, that would have the necessary high level command set that makes features, (like my previous feature suggestions), do-able. The number of new features you could create would be essentially unlimited, assuming a powerful enough command set. Features could be tested and then made integral to the text editor by something like recompilation, allowing for greater execution speed, if speed becomes an issue?
Users could share scripts they created.
Anything you ever wanted in a text editor could be added. :)