anchor.diff:  ;;;;AUTHORS
   ;;;;    <PJB> Pascal J. Bourguignon <pjb@informatimago.com>
   ;;;;MODIFICATIONS
  +;;;;    2014-10-08 <PJB> Corrected step-{break,unbreak}-{entry,exit}.
   ;;;;    2012-08-09 <PJB> Extracted from stepper.lisp
   ;;;;BUGS
   ;;;;LEGAL
   ;;;;    AGPL3
   ;;;;    
  -;;;;    Copyright Pascal J. Bourguignon 2012 - 2012
  +;;;;    Copyright Pascal J. Bourguignon 2012 - 2014
   ;;;;    
   ;;;;    This program is free software: you can redistribute it and/or modify
   ;;;;    it under the terms of the GNU Affero General Public License as published by
  
positive.code: 
  RETURN:         The list of step-break-entry functions remaining.
  "
    `(setf *break-entry-functions* (set-difference *break-entry-functions* ',fnames
                                                   :test (function equal))))
  
  
  
negative.code: 
  RETURN:         The list of function names added.
  "
    `(setf *break-functions-entry*
           (delete-duplicates (union *break-functions-entry* ',fnames
                                     :test (function equal))
                              :test (function equal))))
  
  