From: Jacob Fugal <lukfugl@...>
Date: 2006-08-01T07:54:33+09:00
Subject: Re: I thought this was the one that worked?

On 7/31/06, Chad Perrin <perrin@apotheon.com> wrote:
> On Tue, Aug 01, 2006 at 07:05:31AM +0900, Logan Capaldo wrote:
> > I'm not sure I understand your question. All blocks (by blocks I mean
> > do / end and { } ) are (lexically scoped) closures.
>
> I'll use a Perl example:
>
> sub foo {
>   my $bar = 1;
>   return sub { print ++$bar };
> }
>
> my $baz = foo();
>
> Voila.  $baz contains a lexical closure.  This is the case because the
> return value from foo() was lexically "closed" by virtue of $bar going
> out of scope, but its value still being accessible via the coderef
> returned from foo() and assigned to $baz.

How is this different from:

  def foo
    bar = 1
    return proc{ bar += 1; puts bar }
  end

  begin
    puts bar
  rescue Exception => e
    puts e
  end
  # => undefined local variable or method `bar' for main:Object

  baz = foo
  baz.call # => 2
  baz.call # => 3
  baz.call # => 4
  ...

Jacob Fugal