February 2011: We have decided to provide the
draft of "How to Design Classes" (pdf) on an
"as is" basis for now. You are free to download and print it.
Since we may occasionally fix typos and add material, we recommend that
you do not copy the file. Instead, link to it.
Warning: If we decide to publish the book after all, it is likely that
the publisher will ask us to remove this version of the book from the
web.