From: "T. Onoma" <transami@...>
Date: 2004-08-23T02:16:54+09:00
Subject: Re: Callback for instance var creation?

On Sunday 22 August 2004 06:40 am, Robert Klemme wrote:
> > are "instantiated" upon use and set to nil.
>
> No, they are instantiated on first assignment:
> >> class Foo;end

Oh! I didn't realize b/c if you assign from one that doesn't exist, it returns 
nil.

  irb(main):001:0> x=@x
  => nil
  irb(main):002:0> p x
  nil
  => nil

> > I would like to set this to
> > something else dependent on the name of the variable.

> Which problem are you trying to solve?  Usually attribute accessors can do
> what you want.

Actually, its esoteric. I've been thinking about methods as 1st class objects. 
At one point I have suggested that constants be used. See:

  http://www.rubygarden.org/ruby?FirstClassMethods

But constants are class-level while methods are actually instance level 
(strangely enough). So I thought if they were instance level perhaps an 
instance variable would be better. Using the capitalization idea from before, 
something like:

  def ameth(x)
    puts x
  end

  p @Ameth  # => #<Method: Object#ameth>

So I was trying to auto-assign @Ameth.

> Other than that if you need to intercept all variable settings a modified
> Hash might be better for managing your instance vars:

Perhaps something like that would be better. I'll give it some thought.

Thanks!
T.