> ((list-recur list '()) '(1 2 3))
'(1 (2 (3 ())))
> (map list '(1 2 3))
'((1) (2) (3))
> (define add1 (list-recur add1 '()))
> (add1 '(2 3 4))
. . add1: arity mismatch;
 the expected number of arguments does not match the given number
  expected: 1
  given: 2
> (define add1 (list-recur (lambda (x y) (cons (+ x 1) y)) '()))
> (add1 '(1 2 3))
'(2 3 4)
> (define count (list-recur (lambda (x y) (+ y 1)) 0))
> (count '(1 2 1 1))
4
> (define reverse (list-recur (lambda (x y) (cons y x)) '()))
> (reverse '(a b c))
'(((() . c) . b) . a)
> (define reverse (list-recur (lambda (x y) (append y x)) '()))
> (reverse '(a b c))
. . append: contract violation
  expected: list?
  given: 'c
> (define reverse (list-recur (lambda (x y) (append y (list x))) '()))
> (reverse '(a b c))
'(c b a)
> (define flatten (list-recur (lambda (x y)(cons x y)) '()))
> (flatten '((2 3) 4 ((5))))
'((2 3) 4 ((5)))
> 


> (define sum (snlist-recur + + 0))
> (sum '((2 3) 4 ((5))))
14
> (define count (snlist-recur + (lambda (x y) (+ y 1)) 0))
> (count '((2 3) 4 ((5))))
4
> (define reverse (snlist-recur (lambda (x y) (cons y x)) (lambda (x y) (cons y (list x)))    '()))
> (reverse '((2 3) 4 ((5))))
'(((() () () 5) 4) (() 3) 2)
> (define reverse (snlist-recur (lambda (x y) (append y x)) (lambda (x y) (cons y (list x)))    '()))
> (reverse '((2 3) 4 ((5))))
'((() 5) 4 (() 3) 2)
> (define reverse (snlist-recur (lambda (x y) (append y x)) (lambda (x y) (append y (list x))) '()))
> (reverse '((2 3) 4 ((5))))
'(5 4 3 2)
> (define reverse (snlist-recur (lambda (x y) (cons y x)) (lambda (x y) (append y (list x))) '()))
> (reverse '((2 3) 4 ((5))))
'((() () 5 4) 3 2)
> (define reverse (snlist-recur (lambda (x y) (append y (list x))) (lambda (x y) (append y (list x))) '()))
> (reverse '((2 3) 4 ((5))))
'(((5)) 4 (3 2))
> 

> (expression? 'a)
#t
> (expression? 3)
#f
> (expression? '(lambda (x) x))
#t
> (expression? '(lambda (x) 3))
#f
> (expression? '((lambda (x) x) y))
#t
> (expression? '(lambda x))
#f
> (expression? '(a b))
#t
> lambda
. lambda: bad syntax in: lambda
> a
. . a: undefined;
 cannot reference an identifier before its definition
> '(lambda x)
'(lambda x)
> (car '(lambda x))
'lambda
> '(+ 3 4)

'(+ 3 4)
> (define lambda 3)
> lambda
3
>