代码语言：racket

所属分类：数组

代码描述：racket struct与list操作示例代码

代码标签： list 操作 示例

下面为部分代码预览，完整代码请点击下载或在bfwstudio webide中打开

#lang racket
(struct dog (name breed age))
(define my-pet
  (dog "lassie" "collie" 5))
my-pet ; => #<dog>
; returns whether the variable was constructed with the dog constructor
(dog? my-pet) ; => #t
; accesses the name field of the variable constructed with the dog constructor
(dog-name my-pet) ; => "lassie"

; You can explicitly declare a struct to be mutable with the #:mutable option
(struct rgba-color (red green blue alpha) #:mutable)
(define burgundy
   (rgba-color 144 0 32 1.0))
(set-rgba-color-green! burgundy 10)
(rgba-color-green burgundy) ; => 10

;;; Pairs (immutable)
;; `cons' constructs pairs, `car' and `cdr' extract the first
;; and second elements
(cons 1 2) ; => '(1 . 2)
(car (cons 1 2)) ; => 1
(cdr (cons 1 2)) ; => 2

;;; Lists

;; Lists are linked-list data structures, made of `cons' pairs and end
;; with a `null' (or '()) to mark the end of the list
(cons 1 (cons 2 (cons 3 null))) ; => '(1 2 3)
;; `list' is a convenience variadic constructor for lists
(list 1 2 3) ; => '(1 2 3)
;; a quote can also be used for a literal list value
'(1 2 3) ; => '(1 2 3)
;; .........完整代码请登录后点击上方下载按钮下载查看

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