Gang of Four: lexi editor c++ source

Question

I'm reading "Design Patterns: Elements of Reusable OOSW". In chapter two, the authors provide a case study of an editor they refer to as Lexi, which seems to be written in C++. I've looked around everywhere, but the only useful link I could find said this:

The Gof tell us in a note that Lexi is based on "Doc, a text editing application developed by Calder". But this paper only outlines an editor, without any source. And I even believe today that Lexi never truly existed as a program.

The link provides Delphi source. I'm after C++, cause that's what I'm comfortable with, and that's what's used in the book.

Does anybody know where I can find C++ source for Lexi? If the original never existed, it would be good to find something that I can use as a base. I really don't feel like writing my own text editor from scratch just so I can work through the case study in this book.

Answer 1

Doc was developed using the InterViews UI toolkit. I believe that doc source is part of the InterViews distribution. Doc was used to typeset Paul's thesis. (Paul Calder was my lecturer at Flinders University)

If you look at the InterViews code you might be surprised. It was developed before modern C++ existed. For example, there are no templates. And there are no comments in the code.

To my understanding, Lexi never existed. It was created as an example for the book by GoF.