From: Rick DeNatale <rick.denatale@...>
Date: 2010-06-11T07:45:16+09:00
Subject: Re: Why private #binding?

On Thu, Jun 10, 2010 at 5:08 PM, Yukihiro Matsumoto <matz@ruby-lang.org> wrote:
> Hi,
>
> In message "Re: Why private #binding?"
>    on Fri, 11 Jun 2010 04:57:32 +0900, Intransition <transfire@gmail.com> writes:
>
> |It doesn't recognize it's receiver?
>
> binding returns the binding object that has info on
>
>  * the receiver
>  * local variables
>  * etc.
>
> but invoking it from public form does not explain the context except
> for the receiver.
>
>                                                        matz.

Yes, actually my initial thought about self was the only thing that a
non-private binding method would get 'right'.

The real issue, I think, is that objects in general don't have
bindings, invocations do. Making Kernel#binding private means that
unless you resort to trickery, it will only occur in the context of an
invocation.

Here's a better example:

def test(code)
  x = 1
  b = "abc".send(:binding)
  eval(code, b)
end

test("self") # => "abc"
test("x")    # => 1

The variable x has nothing to do with the string "abc".


"abc".instance_eval  is a better choice if you want to bind self in an
evaluated string or block.
-- 
Rick DeNatale

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