anchor.diff:  (deftest drain (list)
     (assert-equal '((1 2) (3 4))
   		(w/instring in "(1 2) (3 4)"
  -		  (drain (read in nil nil))))
  +		  (drain (read :from in :eof nil))))
     (assert-equal '(128 64 32 16 8 4 2)
   		(let x 256
   		  (drain (= x (/ x 2)) 1)))
  
positive.code: 				:key #'car
  				:start 3))))
  
  ;;; list
  
  (deftest range (list)
    (assert-equal '(1 2 3 4 5) (range 1 5))
  
negative.code: (defsuite conditionals (clamp))
  (defsuite print (clamp))
  
  ;;;; Tests for base.
  
  (deftest literal-fn (base)
    (assert-equal (range 1 10) (map [+ _ 2] (range -1 8))))
  
  (deftest single (base)
    (assert-true  (single '(a)))
  