anchor.diff:            nil
   	(single clauses)
             (car clauses)
  -	'else
  +	:else
           (let (t1 c1 . rest) clauses
   	  `(mvb (,val ,win) ,t1
   	     (if (or ,val ,win)
  
positive.code: ;;;; these are different kinds of conditionals
  
  (in-package "CLAMP")
  
  (mac iflet (var expr &body branches)
    "Same as if but if a predicate is true, it is bound to var"
  
negative.code:         t
        (no (cdr args))
          (car args)
        :else
          `(let it ,(car args)
  	   (declare (ignorable it))
  	   (and it (aand ,@(cdr args))))))
  