anchor.diff:          	      (or (digit-alpha-p #\a)
   				      (digit-alpha-p #\A)))))))
   
  -(defun alphanumericp (c)
  -  "Return T if character is alphabetical."
  +(def-rest-predicate alphanumericp c ()
     (or (alpha-char-p c)
         (digit-char-p c)))
  
positive.code:     			 (character+ c (character- #\a #\A))
      			 c)))
  
  ;XXX error on c-transpiler call if base has no init.
  (defun digit-char-p (c &optional (base 10))
    "Return T if character is a digit."
    (labels ((digit-p ()
               (range-p c #\0 #\9))
             (digit-alpha-p (start)
  
negative.code: ;;;; TRE environment
  ;;;; Copyright (C) 2005-2006,2008-2010 Sven Klose <pixel@copei.de>
  
  (defun char-upcase (c)
    "Return upper case equivalent of lower case character."
  