Your own Lisp

The best way to follow this book is to, as the title says, write your own Lisp. If you are feeling confident enough I want you to add your own features, modifications and changes. Your Lisp should suit you and your own philosophy. Throughout the book I’ll be giving description and insight, but with it I’ll be providing a lot of code. This will make it easy to follow along by copy and pasting each section into your program without really understanding. Please do not do this!.

Type out each piece of sample code yourself. This is called The Hard Way. Not because it is hard technically, but because it requires discipline. By doing things The Hard Way you will come to understand the reasoning behind what you are typing. Ideally things will click as you follow it along character by character. When reading you may have an intuition as to why it looks right, or what may be going on, but this will not always translate to a real understanding unless you do the writing yourself!

In a perfect world you would use my code as a reference - an instruction booklet and guide to building the programming language you always dreamed of. In reality this isn’t practical or viable. But the base philosophy remains. If you want to change something, do it.