anchor.diff:  (proclaim '(ftype (function (symbol) t)
   	    boundp))
   
  -(proclaim '(ftype (function (&optional (or string function)) &rest list) null
  +(proclaim '(ftype (function (&optional (or string function) &rest list) nil)
   	    break))
   
   (proclaim '(ftype (function (broadcast-stream) list)
  
positive.code: (proclaim '(ftype (function (cell-error) t)
  	    cell-error-name))
  
  (proclaim '(ftype (function ((or string function) &rest list) null)
  	    cerror))
  
  (proclaim '(ftype (function (t (or symbol class) &key &allow-other-keys) t)
  
negative.code: (proclaim '(ftype (function (t t) cons)
  	    cons))
  
  (proclaim '(ftype (or
  		   (function (cons) (eql t))
  		   (function (atom) null))
  	    consp))
  
  (proclaim '(ftype (function (t) (function ()))
  