anchor.diff:  ;;;;LEGAL
   ;;;;    AGPL3
   ;;;;
  -;;;;    Copyright Pascal J. Bourguignon 2012 - 2021
  +;;;;    Copyright Pascal J. Bourguignon 2012 - 2022
   ;;;;
   ;;;;    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:         (if (member (first function-name)
                      '(com.informatimago.common-lisp.lisp.stepper:lambda lambda))
              `(progn
                 ;; (print '(2) *step-trace-output*)
                 (simple-step `(,(step-lambda function-name :environment env)
                                 ,@(mapcar (lambda (argument) (step-expression argument env))
                                           arguments))
                              form))
              (error "Invalid object used as function name ~S in function call ~S"
                     function-name form))
          `(progn
             ;; (print '(3) *step-trace-output*)
             ,(simple-step `(,function-name
                             ,@(mapcar (lambda (argument) (step-expression argument env))
                                       arguments))
                           form)))))
  
  
  (defun step-expression (form env)
    ;; Operators in CL-STEPPER are macros, so they're taken care of
  
negative.code:              (did-step display-form results)
               (values-list results))))
      (case *step-mode*
        ((:run :function) (funcall thunk))
        (:trace  (with-parens *step-trace-output* (do-step)))
        (:step   (with-parens *step-trace-output*
                   (doagain
  