scheme - How to delete the first and last elements of a list? -


i'm trying remove both first , last elements of list in racket. there other way of doing instead of:

(cdr (reverse (cdr (reverse my-list)))) 

here's 1 way it, using racket's built-in procedures:

(define my-list '(1 2 3 4 5 6 7 8 9 10))  (drop-right (rest my-list) 1) => '(2 3 4 5 6 7 8 9) 

note: can use cdr instead of rest, rest more idiomatic in racket. more general solution:

; remove `left` number of elements elements left side ; , `right` number of elements right side of list (define (trim lst left right)   (drop-right (drop lst left) right))  (trim my-list 1 1) => '(2 3 4 5 6 7 8 9)  (trim my-list 2 4) => '(3 4 5 6) 

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