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|
#|
multiline
comment
|#
"string with special \n \t chars"
; comment
(define (fn a)
(let* ((b (+ a 1)))
(if (= a 1)
#t
#f))) ;; another comment
(define c (lambda (x)
(let loop ((i 0))
(unless (= i 10)
;; print some chars
(display #\' #\#)
(loop (+ i 1))))))
((if (= 0 0) * +) 5 2)
;; numbers
(define pi 3.14159)
(define circle-area
(lambda (radius)
(* pi radius radius)))
(define (circle-area radius)
(* pi radius radius))
(define (blah)
(define (foo) 55)
(define (woo) 42)
(+ (foo) (woo)))
(define (repeat-forever)
(display "I will not play with Scheme in class.")
(repeat-forever))
(define (all-atoms-are-numeric? tree)
(call-with-current-continuation
(lambda (return) ;bind RETURN to the current cont
(define (walk tree)
(cond ((null? tree))
((pair? tree) ;pair? is like consp
(walk (car tree))
(walk (cdr tree)))
((number? tree))
(else (return #f)))) ;found a non-number -- return false
(walk tree)
#t))) ;else return true
(cond ((number? x) "A number.")
((string? x) "A string.")
(else "Beats me!"))
(cond ((assoc key a-list) => cdr)
(else #f))
(letrec ((even? (lambda (n) (if (= n 0) #t (odd? (- n 1)))))
(odd? (lambda (n) (if (= n 0) #f (even? (- n 1))))))
(even? 42))
(let counting ((n 10))
(cond ((< 0 n)
(write n)
(counting (- n 1)))))
(define (list . arguments) arguments)
(define-syntax my-or
(syntax-rules ()
((my-or) #f)
((my-or e) e)
((my-or e1 e2 ...)
(let ((temp e1))
(if temp temp (my-or e2 ...))))))
(define-syntax syntax-rules
(lambda (x)
(syntax-case x ()
((_ (i ...) ((keyword . pattern) template) ...)
(syntax (lambda (x)
(syntax-case x (i ...)
((dummy . pattern) (syntax template))
...)))))))
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