Very Advanced Structures

This page describes advanced features. You should already be familiar with writing code in #lang racket and using #:transparent when defining a struct.

Figure out how to install a package in Racket by looking in the menu under File -> Install Package…

Install the struct-update package.

Read about how to use define-struct-updaters in the help desk.

Example:

#lang racket
(require struct-update)
(define-struct game (id pts loc) #:transparent)
(define-struct-updaters game)

(require picturing-programs)

(define ex1 (make-game 10 21 "upper left"))

ex1

(game-loc-set ex1 "lower left") ;; (make-game 10 21 "lower left")
(game-pts-update ex1 add1)      ;; (make-game 10 22 "upper left")