Minor pedantry: Most variants of Lisp are not precisely a serialization of the AST. The read engine and macro engines have to pass over the code before it is t

Minor pedantry: Most variants of Lisp are not precisely a serialization of the AST. The read engine and macro engines have to pass over the code before it is truly an AST. For Common Lisp I believe technically either can be invoked at any time, but I am not a Common Lisp language lawyer.