From: Francis Hwang <sera@...>
Date: 2005-05-29T12:05:53+09:00
Subject: Re: preventing Object#send from dispatching to a global method?

Okay, thanks for the tip, that's definitely giving me some ideas. 
Builder::BlankSlate's strategy seems like something for me to follow. 
Here's an added piece of complexity: this logic has to depend on values 
set during the class definition. I'm talking, BTW, about Lafcadio's 
DomainObjects. So:

def fname; "here's an unfortunate coincidence"; end

class User < Lafcadio::DomainObject
   text 'fname'
   text 'lname'
end

I wanted to trigger some methods to undefine instance methods of 
'fname' in User, but I can't do that with Class.inherited -- because at 
the time that the User class is being defined, I don't know that I'm 
looking for global methods named 'fname' and 'lname'.

It feels like, from perusing the archives, there is currently no way to 
be notified when a class definition is finished. Correct?


On May 28, 2005, at 10:29 PM, Jim Weirich wrote:

>
> On May 28, 2005, at 11:42 AM, Francis Hwang wrote:
>
>> Is there a way to prevent Object#send from dispatching to a global 
>> method? By which I mean:
>>
>
> You could look at how Builder::BlankSlate handles it.  It uses method 
> defined hooks to undefine any methods added to any ancestors.  You can 
> find BlankSlate in the builder gem.
>
> For example
>
> traken$ irb --simple-prompt
> >> require 'builder/blankslate'
> => false
> >> class Empty < Builder::BlankSlate
> >>  def inspect
> >>   "<empty>"
> >>  end
> >>  def method_missing(sym, *args)
> >>   puts "Calling #{sym}(#{args.join(',')})"
> >>  end
> >> end
> => nil
> >> e = Empty.new
> => <empty>
> >> e.hi
> Calling hi()
> => nil
> >> def hi() "HI" end
> => nil
> >> e.hi
> Calling hi()
> => nil
>
>

Francis Hwang
http://fhwang.net/