From: k <kturing@...>
Date: 2002-05-28T18:41:40+09:00
Subject: Re: confused about scope of block parameter

I wrote:
> It outputs "OuterOuter". I expected "InnerOuter".

Oops. I typed badly. It does in fact output "InnerInner". But the question
still remains.

"k" <kturing@yahoo.com> wrote in message
news:ZQHI8.123742$UV4.223942@rwcrnsc54...
> I'm not certain how to word this question precisely. So I'll begin with an
> example.
> Consider this bit of Ruby:
>
>    foo = "Outer"
>    (lambda {|foo| print foo}).call("Inner")
>    print foo
>
> It outputs "OuterOuter". I expected "InnerOuter". I thought that this
would
> be equivalent to the following bit of Lisp, which does output
"InnerOuter":
>
>    (let ((foo "Outer"))
>      (funcall (lambda (foo) (format t foo)) "Inner")
>      (format t foo))
>
> Can someone explain the Ruby behavior here? Is the block parameter foo
> really bound to the containing scope's foo variable? Or am I missing
> something very basic? Why would it work this way instead of creating a new
> foo in the block's new scope?
>
> Thanks!
> k
>
>