From: Gennady <gfb@...>
Date: 2004-08-11T05:29:29+09:00
Subject: Re: Singleton class methods

Robert Klemme wrote:
> "Gennady" <gfb@tonesoft.com> schrieb im Newsbeitrag
> news:4118FEE9.10002@tonesoft.com...
> 
>>Kyle Putnam wrote:
>>
>>>Hello,
>>>
>>>It seems these two syntaxes accomplish the same thing, or are there
>>>differences?
>>>
>>>    class Foo
>>>        class << self
>>>            def bar
>>>                # ...
>>>            end
>>>        end
>>>    end
>>>
>>>compared to...
>>>
>>>    class Foo
>>>        def Foo.bar
>>>            # ...
>>>        end
>>>    end
>>>
>>>Cheers,
>>>    Kyle
>>>
>>>
>>
>>Exactly the same from the functionality point of view (it differs in
>>implementation, though).
> 
> 
> Where exactly do you see this difference?

Please see my reply to David Black's message, I really meant to place it 
here, sorry.

> 
> 
>>I personally prefer the first form, as when it
>>comes to renaming a class, you can do it in one place.
> 
> 
> This is also possible with
> 
> class Foo
>   def self.bar
>             # ...
>   end
> end
> 
> I base my decision which idiom to use on the number of methods.  If it's
> just one or two, I usually take the def self.foo approach.

With "class << self" form it is also convenient to fold all class 
methods at once in vim, I like that :-)

> 
> 
>>Also with this
>>form you can do other nice things such as defining class attribute
>>accessors with attr_reader, attr_writer or attr_accessor.
> 
> 
> Yep!
> 
> Kind regards
> 
>     robert
> 
>