> (count-atoms dl)
8
> (atom? '())
#f
> 
> (flatten dl)
[image] [image] mcar: contract violation
  expected: mpair?
  given: 2
> (flatten dl)
(1 2 3 4 5 6 7 8)
> (flatten dl)
(((1) ((2))) ((((3)) (4)) ((5) ((6))) () ((7))) (8))
> (flatten dl)
((1 (2)) (((3) 4) (5 (6)) () (7)) 8)
> (flatten dl)
(1 2 3 4 5 6 7 8)
> 
> (deep-reverse dl)
[image] [image] mcar: contract violation
  expected: mpair?
  given: 2
> (deep-reverse dl)
(8 ((7) () ((6) 5) (4 (3))) ((2) 1))
> dl
((1 (2)) (((3) 4) (5 (6)) () (7)) 8)
> 
> (count-a
> (count-atoms dl)
8
> (flatten dl)
(1 2 3 4 5 6 7 8)
> 
> (deep-reverse dl)
(8 ((7) () ((6) 5) (4 (3))) ((2) 1))
> dl
((1 (2)) (((3) 4) (5 (6)) () (7)) 8)
> (count-atoms dl)
[image] [image] foldr: undefined;
 cannot reference an identifier before its definition
> (count-atoms dl)
[image] [image] mcar: contract violation
  expected: mpair?
  given: 1
> 
> (append '() '(1 2 3) '(4 5 6) '(7 8 9))
(1 2 3 4 5 6 7 8 9)
> (apply + '(1 2 3 4 5))
15
> (apply + 1 2 '(3 4 5))
15
> (count-atoms dl)
8
> (flatten dl)
(1 2 3 4 5 6 7 8)
> (deep-reverse dl)
(8 ((7) () ((6) 5) (4 (3))) ((2) 1))