list - Some misunderstanding between me and Scheme -

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i'm started learning scheme , can't quite understand why function not work:

;(define (sort l)   (define (sorted? l)     (if (= (length l) 2)                     ; if simple list:         (if (< (head l) (tail l))              #t               #f)          ; if complex list:         (if (and (< (head l) (head (tail l)))                   (sorted? (tail l)))             #t               #f)))

output:

(sorted? (1 0)) . . procedure application: expected procedure, given: 1; arguments were: 0 (sorted? '(1 0)) . . <: expects type 2nd argument, given: (0); other arguments were: 1

racket, r5rs

this because compare integer , list, cadr or if (< (head l) (head (tail l))) instead of if (< (head l) (tail l)) after line ; if simple list have more chances work you.

the following definition works me:

(define (sorted? xs)   (cond     ((<= (length xs) 1)      #t)     ((< (car xs) (cadr xs))      (sorted? (cdr xs)))     (else #f)))

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