anchor.diff:     #:with-collector
      #:with-collectors
   
  +   #:form
      #:walk-form
      #:make-walk-env
      #:*walk-handlers*
  
positive.code:    #:the-form
     #:extract-argument-names
     #:walk-lambda-list
  
     #:unwalk-form
  
     #:to-cps
     #:with-call/cc
  
negative.code:    #:and-bind
     #:if2-bind
     #:aif2
  ;; #:while ; iterate
     #:awhile
  ;; #:until ; iterate
     #:it
     #:whichever
     #:xor
  