From: David Colque <d_colque@...>
Date: 2008-08-27T00:19:25+09:00
Subject: Re: Access to method in superclass

RichardOnRails wrote:
> On Aug 25, 2:35 pm, David Colque <d_col...@yahoo.es> wrote:
>> LIKE ACCEDING TO THE METHOD " setSpeed" OF THE SUPERCLASS "Airplane".
>> Thak you
>>
>> Attachments:http://www.ruby-forum.com/attachment/2606/prueba1.rb
>>
>> --
>> Posted viahttp://www.ruby-forum.com/.
> 
> Hi David,
> 
> Your access to Airplane::setSpeed is working.
> 
> On line 55, you create an Airplane::Jet instance with @speed=0
> On line 56, you invoke that setSpeed on the instance with argument 422
>   so the method on line 38 is called with 422
>   which in turn invokes Airplane::setSpeed with the argument
> 422*Multiplier, of 844,
>   which is then set in @speed of the Airplane::Jet instance
> On line 57, you print out the 844
> 
> Then on line 57, you invoke
> 
> Line 56 set the Jet's speed to 0
> Line 57 with argument 422 set the Jet's speed to 422*Multiplier, or
> 844 and printed it
> 
> Line 60 invoked accelerate, which in turn invoked
> Line 45 setSpeed(getSpeed()*2)
>   getSpeed returned your 844, which then got doubled to 1688
>   which was used as the argument to setSpped, which applied the
> Multiplier
>   so the speed was set to 3376
> Line 61 used getSpeed to retrieve the 3376, which then got printed.
> 
> All this is confirmed by lines 2 and 2 of your output.
> 
> HTH,
> Richard

class Jet < Airplane
  MULTIPLIER = 2
  def initialize
    super
  end
  def setSpeed(speed)
    super(speed*MULTIPLIER)
  end
  def accelerate
    # TROUBLE!!!!!!!!
    # LIKE ACCEDING TO THE METHOD " setSpeed"
    # OF THE SUPERCLASS "Airplane"
    Airplane::setSpeed(getSpeed()*2)
  end

end

At the time of making it run it leaves the error
>ruby prueba1.rb
prueba1.rb:28:in `accelerate': undefined method `setSpeed' for 
Airplane:Class (NoMethodError)
  from prueba1.rb:43:in `principal'
  from prueba1.rb:57
212
844
>Exit code: 1
-- 
Posted via http://www.ruby-forum.com/.