On Wed, Dec 19, 2012 at 5:07 PM, Chen Xiao <chenxiao770...@gmail.com> wrote:
> Why racket's class not like Java have a constructor method?
The body of the class can do things that a constructor method can
typically do, including calling the instantiation for the super class.
Example:
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
#lang racket
(define thing%
(class object%
(init-field name)
(super-new)
(printf "making up ~a\n" name)))
(define food%
(class thing%
(init-field calories)
(inherit-field name)
(printf "bubble, bubble...\n")
(super-new)
(printf "Cooking ~a (~a cals)\n" name calories)))
(define t (new thing%
[name "rainbow"]))
(define f (new food%
[name "ramen"]
[calories 56000]))
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
The calls to 'super-new' there are calls to the parent class's initializer code.
Does this do what you want?
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