bes the methods after hook is done to keyDown: method in DVTSourceTextView class.

<h4>initWithCoder</h4>
This is called when a DVTSourceTextView object is initialized. What we want to do in this hook is to bind "Operations" part to this object.
As explained, we hook keyDown: and forward it to "Operations" part (which is a object we make). In the hook method of keyDown: we want to know where is the "operation" object corresponds to the DVTSourceTextView.


<h4>keyDown: and Evaluators</h4>
On each keyDown ev