From: Trans <transfire@...>
Date: 2008-03-26T20:41:00+09:00
Subject: Re: TOPLEVEL_OBJECT



On Mar 26, 5:28 am, "Daniel Brumbaugh Keeney"
<devi.webmas...@gmail.com> wrote:
> This is a Ruby Change Request.http://rcrchive.net/rcrs/19
>
> Ruby lacks a TOPLEVEL_OBJECT constant, which provides access to the
> object resulting from this Ruby expression:
>
> eval( 'self', ::TOPLEVEL_BINDING )
>
> That object is a built-in object of the Ruby programming language,
> which should be accessible from any point in Ruby code. It is
> well-suited to be assigned to a constant. This constant assignment is
> comparable to TOPLEVEL_BINDING, in that, while any library could
> assign the value to a constant, it is an object inherent to the Ruby
> programming language, and therefore should be assigned to a constant
> by the core library.
>
> Specifically, a use case where I found the need to assign
> TOPLEVEL_OBJECT was in a tracing program, where it was helpful to
> exclude certain objects from being traced. TOPLEVEL_OBJECT needed to
> be referenced to be added to the list of exclusions. As previously
> stated, it can be trivially assigned to TOPLEVEL_OBJECT, or found
> dynamically via it's definition above, it should be included in the
> Ruby core, and it is inappropriate for any other library to assign it.

+1

I also would like to ask why Ruby calls this object "main", but does
not use it in any other way.

  $ irb
  >> self
  => main

T.