From: Rob Biedenharn <Rob@...>
Date: 2009-02-05T05:06:55+09:00
Subject: Re: Making object methods available externally

On Feb 4, 2009, at 2:03 PM, David Stanford wrote:
> Rob Biedenharn wrote:
>> On Feb 4, 2009, at 1:37 PM, David Stanford wrote:
>
>> class CheesePhrase
>>   def initialize(phrase)
>>     @phrase = phrase
>>     say_it
>>   end
>>
>>   def self.say_it(phrase)
>>     puts phrase
>>   end
>>   def say_it
>>     self.class.say_it(@phrase)
>>   end
>> end
>
>> -Rob
>>
>> Rob Biedenharn    http://agileconsultingllc.com
>> Rob@AgileConsultingLLC.com
>
> Thanks a lot, Rob. Is this really the standard way of implementing
> something like this? It just seems a little redundant, no?
>
> Thanks!
>
> -David


When you need it, yes. However, it isn't typical that you'd do  
something like this.  Either the method belongs on the instance or it  
belongs on the class itself.  Occasionally, for convenience, you want  
a class method to be called on an instance and then you'd likely do it  
this way. Your example is simple (and, being an example, somewhat  
contrived), but illustrates a point.  You can call #say_it with no  
parameter because the instance variable is there so an instance  
*knows* what to say, but to call .say_it on the class, you need to  
pass the parameter.

-Rob

Rob Biedenharn		http://agileconsultingllc.com
Rob@AgileConsultingLLC.com