The effort will pay dividends in the time you don't spend recovering from lost source code changes. Lisp actually does have a rudimentary system of maintaining file dependencies. I also didn't mention the module system because it has quite limited expressive power. Better yet, some Lisp environments let you dump an image of your Lisp world, which lets you load the system without having source or object files at all. This book may not be reproduced without the written consent of its author.
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