From: Frodo Larik <lists@...>
Date: 2005-08-28T23:58:51+09:00
Subject: Dynamic methods / accessors

Hi all,

I'm trying to setup some kind of dynamic method / accessor assignment to 
objects. But I don't want the other objects from the same class to know 
about "personal" methods. I'm just learning Ruby, so it could be I 
missed something.

For example:

class MyThing
    def create_method(method)
       # I found two things on internet which can acchieve this
       #    self.class.class_eval { attr_accessor method }
       # AND
       #    self.class.send(:define_method, method, &block)
       # but I'm not sure which is the best one to use, but I think
       # I prefer the attr_accessor, because that's the functionality
       # I need
    end
end


# Create first object
a = MyThing.new
a.create_method('box')       # Adds a method box to a
a.box = 'something inside'

# The nicest thing would be if I could do something like this:
a.create_method('box','some_value'), so a.box is populated with 'some value'


# Create second object
b = MyThing.new

# I don't want the following to happen
b.box = 'something other'

I don't want the method 'box' be available to b, only to a

How can I achieve this?

I saw it was possible to achieve this with something like this:

class YourThing < MyThing
    # A placeholder class for the dynamic methods
end

but I don't know the name of the class on forehand, so if something like 
this is possible:

class #{i_want_this_class} < MyThing
    # A placeholder class for the dynamic methods
end

That would be nice.





Sincerely,

Frodo Larik