anchor.diff:  ; tré – Copyright (c) 2014–2015 Sven Michael Klose <pixel@copei.de>
   
  +(defvar *special-forms* nil)
  +
   (defun special-%%macrocall (x)
  -  (alet (cdr (assoc x. *macros* :test #'eq))
  +  (alet (cdr (assoc x. *special-forms* :test #'eq))
       (apply .! (argument-expand-values x. !. .x))))
   
   (defun special-%%macro? (x)
     (& (cons? x)
        (symbol? x.)
  -     (assoc x. *macros* :test #'eq)))
  +     (assoc x. *special-forms* :test #'eq)))
   
   (defun specialexpand (x)
     (with-temporaries (*macro?-diversion*    #'special-%%macro?
  
positive.code:     (with (f #'((old x)
                   (? (equal old x)
                      x
                      (specialexpand x))))
        (f x (%macroexpand x)))))
  
  (defun make-%defun-quiet (name args body)
  
negative.code:                (. ',args
                    #'(,(argument-expand-names '%defmacro args)
                      ,@body)))
              ,(tre-symbol '*macros*)))
  
  (defspecial %defvar (name &optional (init nil))
    (print-definition `(%defvar ,name))
  