From: Andrea Dallera <andrea@...>
Date: 2010-03-15T23:41:57+09:00
Subject: Re: Overriding new?

Hei Chuck,

	that's exactly what i was trying to avoid. While I'm at it, let me be
more specific about my problem, which is actually not just printing out
text to the console but changing the state of the newly created
instance:

class Parent

  attr_reader :test_value
  
  def initialize
    @test_value = "from parent"  
  end

end

class Child < Parent

  def initialize
    p @test_value    
  end
	
end

child = Child.new

this should print out "from parent"

-- 
Andrea Dallera
http://github.com/bolthar/freightrain
http://usingimho.wordpress.com


On Mon, 2010-03-15 at 23:32 +0900, Chuck Remes wrote:
> On Mar 15, 2010, at 9:13 AM, Andrea Dallera wrote:

> > Hi everybody,
> > 
> > 	given the following situation:
> > 
> > class Parent
> > 
> >  def initialize
> >    print "magic\n"
> >  end
> > 
> > end
> > 
> > class Child < Parent
> > 
> >  def initialize
> >    print "more magic\n"
> >  end
> > 
> > end
> > 
> > child = Child.new
> > 
> > is there a way in which i can get "magic" and "more magic" as the
> > output, without having to add super to the child class's constructor? I
> > was thinking about overriding the class method "new" but i really didn't
> > get anything to work up to now. 
> 
> Use the #super keyword to call the superclass.
> 
> 
> class Parent
>   def initialize
>     print "magic\n"
>   end
> end
> 
> class Child < Parent
>   def initialize
>     super
>     print "more magic\n"
>   end
> end
> 
> child = Child.new
> 
> ----------
> 
> cremes$ ruby a.rb
> magic
> more magic
> 
> cr
> 
>