From: Zach Dennis <zdennis@...>
Date: 2005-05-29T13:33:52+09:00
Subject: Re: Thankyou caio

Navya Amerineni wrote:
> Hi caio,
> 
>    thanks for your valuble suggestion and it works
> great.I have one another silly question
> 
> this is the code
> class Song
> def initialize(name, artist, duration)
> 	@name=name
> 	@artist=artist
> 	@duration=duration
> end
> def myclass_function
> 	puts "this is my first class"
> end
> def to_s
> 	puts "Song: #@name--#@artist (#@duration)"
> end
> end
> class Karaokesong
> def initialize(name, artist, duration, lyrics)
> 	super(name, artist, duration)
> 	@lyrics=lyrics
> end
> def to_s
> 	puts "Song: #@name--#@artist (#@duration)"
> end
> end
> 
> the following is the error
> 
> "myfirstprojectfile:16:in `initialize': wrong number
> of arguments (3 for 0) (ArgumentError)"
> 
> the error is with super.
> 
> can you explain why it is.

Change the following line:
    class Karaokesong
to:
    class Karaokesong < Song

That will make Karaokesong a subclass of Song. When you call super it 
will call Song's initialize method which takes 3 arguments. When it 
doesn't subclass Song, Karaokesong by default will subclass from Object. 
Object itself doesn't take any arguments in it's constructor.

HTH,

Zach