From: Meinrad Recheis <meinrad.recheis@...>
Date: 2003-05-08T14:48:58+09:00
Subject: Re: access a variables name?

Mauricio Fern�ndez wrote:
[...]

>batsman@tux-chan:/tmp$ expand -t2 ac.rb
>
>class Foo
>  def iv_name(iv)
>    instance_variables.each do |x|
>      return x if instance_eval(x).id == iv.id
>    end
>    nil
>  end
>
>  def dump(var, subst = false)
>    name = iv_name(var)
>    return name if name && subst
>    case var
>    when Array
>      "[" + var.map {|x| self.dump(x,true)}.join(",") + "]"
>    when Hash
>      "{" + var.map {|k, v| self.dump(k,true) + "=>" + 
>                            self.dump(v,true)}.join(",") + "}"
>    else
>      var.inspect
>    end
>  end
>end
>
>file = <<-EOF
>@var1 = [1,2]
>@var2 = {1=>@var1}
>@var3 = {@var1 => @var2}
>EOF
>
>someobj = Foo.new
>someobj.instance_eval file
>
>puts "Reconstructed file:"
>someobj.instance_variables.sort.each do |x|
>  repr = someobj.dump(someobj.instance_eval(x))
>  puts "#{x} = #{repr}"
>end
>
>  
>
thank you, that s very helpful.

>batsman@tux-chan:/tmp$ ruby ac.rb
>Reconstructed file:
>@var1 = [1,2]
>@var2 = {1=>@var1}
>@var3 = {@var1=>@var2}
>  
>
[..]

- m.r.