From: Yuh-Ruey Chen <maian330@...>
Date: 2008-11-01T06:18:57+09:00
Subject: Re: How to access to local variables in enclosing scopes?

On Oct 31, 3:09 pm, Stefan Lang <perfectly.normal.hac...@gmail.com>
wrote:
> 2008/10/31 Yuh-Ruey Chen <maian...@gmail.com>:
>
> > Well then just wrap that example in another function:
>
> > def scope()
> >        a = 20
> >        def foo():
> >                a = 10
> >                def bar():
> >                        print a # prints 10
> >                bar()
> >        foo()
> >        print a # prints 20
> > scope()
>
> FWIW, Ruby doesn't have nested procedures like that.

According to my copy of Ruby, it does.

> > I am trying to understand Ruby with some metaprogramming practice. But
> > I still feel that this is a really backwards step in language design.
>
> > It's like telling me I should use GOTO in original BASIC instead of
> > trying to bend the language to simulate while loops. Would any sane
> > modern programmer do that?
>
> I don't think it's a good analogy. Ruby is more oriented towards
> little objects and message passing than Pascal-like nested
> procedures.

Then why the first-class code blocks? Certainly makes Ruby a
functional language, if only for blocks.

> I'm sure we could work out an elegant solution to some higher
> level goal than "accessing local variables", especially when it
> comes to metaprogramming.

The ability to access local vars in enclosing scopes is strictly
unnecessary. But the same could also be said for instance_variable_get/
defined?/set.