From: Josef Wolf <jw@...>
Date: 2009-09-09T19:57:33+09:00
Subject: How to get the return value from method of the super class?

Hello,

I am trying to override a method of a superclass within my derived class.
To do the real work, I need to call the original method of the superclass.
But when I try to get the return value of the super method, I only get
the object, not the return values I expected.  Here's a code snippet to
demonstrate the problem, stripped from everything not related to the
problem:

jw@raven> cat ./test.rb
#! /usr/bin/ruby

require 'tk'
require 'pp'

root = TkRoot.new { title "pcb.rb" }

class TkDerivedCanvas < TkCanvas
  def coords(tag, *args)
    super(tag, args)
  end
end

orig    = TkCanvas.new(:scrollregion=>[0,0,500,400]).pack()
derived = TkDerivedCanvas.new(:scrollregion=>[0,0,500,400]).pack()

origrect    = TkcRectangle.new(orig,    [100,100], [300, 200], :fill=>"red")
derivedrect = TkcRectangle.new(derived, [100,100], [300, 200], :fill=>"red")

pp orig.coords(origrect)
pp derived.coords(derivedrect)

jw@raven> ./test.rb
[100.0, 100.0, 300.0, 200.0]
#<TkDerivedCanvas:0xb7cce11c @path=".w00001">
jw@raven> 


Any ideas what I am doing wrong here?