The Changed Definitions view allows you to see which definitions have been edited in the current session.
Edit some of the definitions in the Othello game example in
examples/capi/applications/othello.lisp and then click on the
tab. The Editor appears as shown in The Changed Definitions view in the Editor below.
Figure 13.6 The Changed Definitions view in the Editor
Notice that the Changed Definitions view is similar to the Definitions view. The Editor's Works > Definitions menu, and the filter box, can be used on definitions listed here in the same way as in the Definitions view.
The Changed Definitions view has an additional area labelled Show definitions changed since: . This allows you to change the reference point against which the current buffer is compared when computing the changes.
The state of the buffer just before you first edited it in the current LispWorks session. This is the initial reference point.
The state of the buffer when you last saved it to file
The state of the buffer when you last compiled it.
LispWorks IDE User Guide (Windows version) - 13 Sep 2017