anchor.diff:  ;;;;;;;;;;;;;;;; undefined reader macro
   
   ;;; parse trees
  -(defclass undefined-reader-macro-form (form) ())
  +(defclass undefined-reader-macro-form (form complete-form-mixin) ())
   
   (define-parser-state |#<other> | (form-may-follow) ())
   (define-parser-state |#<other> form | (lexer-toplevel-state parser-state) ())
  
positive.code: ;;;;;;;;;;;;;;;; sharpsign equals
  
  ;;; parse trees
  (defclass sharpsign-equals-form (form) ())
  
  (define-parser-state |#= | (form-may-follow) ())
  (define-parser-state |#= form | (lexer-toplevel-state parser-state) ())
  
negative.code: ;;;;;;;;;;;;;;;; readtime evaluation
  
  ;;; parse trees
  (defclass readtime-evaluation-form (form complete-form-mixin) ())
  
  (define-parser-state |#. | (form-may-follow) ())
  (define-parser-state |#. form | (lexer-toplevel-state parser-state) ())
  