anchor.diff:  (defun %format-directive (inf txt args)
     (++! (format-info-processed-args inf))
     (case (char-upcase txt.) :test #'character==
  -    #\% (%format-directive-eol inf .txt args)
  -    #\A (%format-directive-placeholder inf .txt args)
  -    #\F (%format-directive-force-output inf .txt args)
  +    #\%  (%format-directive-eol inf .txt args)
  +    #\A  (%format-directive-placeholder inf .txt args)
  +    #\F  (%format-directive-force-output inf .txt args)
  +    #\~  (%format-char inf txt args)
       (%format-directive-tilde inf txt args)))
  +
  +(defun %format-char (inf txt args)
  +  (princ txt. (format-info-stream inf))
  +  (%format inf .txt args))
   
   (defun %format (inf txt args)
     (when txt
  
positive.code:                                   (princ .txt. !)
                                    (%format inf ..txt args))
          (character== txt. #\~)  (%format-directive inf .txt args)
          (progn
            (princ txt. !)
            (%format inf .txt args))))))
  
  (defun format (str txt &rest args)
    (with-default-stream nstr str
      (with-temporary *print-automatic-newline?* nil
        (%format (make-format-info :stream nstr :text txt :args args) (string-list txt) args))))
  
negative.code: ; tré – Copyright (c) 2006–2008,2011–2013,2015 Sven Michael Klose <pixel@copei.de>
  
  (defstruct format-info
    stream
  