;; CSE 413 21sp Lecture 1
;; DrRacket interactions window

Welcome to DrRacket, version 8.0 [cs].
Language: racket, with debugging; memory limit: 128 MB.
> 17
17
> "hello"
"hello"
> 5/3
1 2/3
> 1/3
1/3
> 0.333333
0.333333
> 1+2
. . 1+2: undefined;
 cannot reference an identifier before its definition
> (+ 1 2)
3
> (+ 1 2 3 4 5 6)
21
> (* 3 5 7)
105
> (- 4 2)
2
> (/ 1 3)
1/3
> (/ 1.0 3.0)
0.3333333333333333
> +
#<procedure:+>
> (+ 1 2.0)
3.0
> (/ 1 3.0)
0.3333333333333333
> (/ 1 3)
1/3
> (* 2 (+ 1 2))
6
> (* 2 (/ 1 3))
2/3
> (+ 2 1)
3
> (+ 2 (* 3 4))
14
> (define panda 5)
> panda
5
> (+ panda 1)
6
> (+ zebra 2)
. . zebra: undefined;
 cannot reference an identifier before its definition
> (define zebra 1234)
> zebra
1234
> (* zebra panda)
6170
> (define (twice n) (* 2 n))
> twice
#<procedure:twice>
> +
#<procedure:+>
> (twice panda)
10
> panda
5
> (twice (twice (twice 2)))
16
>