From: David Chelimsky <david@...>
Date: 2006-07-13T19:24:10+09:00
Subject: Re: re-define class method

Well, I discovered the solution, thanks to our friend google, and got  
a much better understanding of singleton classes (though the fog  
hasn't completely dissipated). For anyone interested:

thing_singleton_class = class << Thing; self; end
thing_singleton_class.send(:define_method, :class_method, proc  
{ "replaced" })

Thing.class_method
=> "replaced"

Cheers,
David

On Jul 12, 2006, at 10:08 PM, David Chelimsky wrote:

> On Jul 12, 2006, at 9:58 PM, David Chelimsky wrote:
>
>> I've got the following:
>>
>> module ClassMethods
>>   def class_method
>>     "Class method"
>>   end
>> end
>>
>> class Thing
>>   extend ClassMethods
>> end
>>
>> Thing.class_method
>> => "Class method"
>>
>> ... and I want to change the behaviour of that method at runtime.  
>> I tried this:
>>
>> Thing.send(:define_method, :class_method, lambda{ "replaced" })
>>
>> ... but I still get this:
>>
>> Thing.class_method
>> => "Class method"
>>
>> Am I close? What's the right way to do this?
>
>
> OK - I've discovered that I can do this:
>
> Thing.class.send(:define_method, :other_method, lambda{ "other" })
> Thing.other_method
> => "other"
>
> and even redefine it:
>
> Thing.class.send(:define_method, :other_method, lambda{ "other  
> redefined" })
> Thing.other_method
> => "other redefined"
>
> but if I try this:
>
> Thing.class.send(:define_method, :class_method, lambda{ "replaced" })
> Thing.class_method
> => "Class method"
>
> So it looks like I can replace class methods that I define at  
> runtime, but not the ones that were defined at load-time. Is that  
> correct? Am I missing a step?
>
> Thanks,
> David
>
>
>