From: ahoward <ahoward@...>
Date: 2003-01-30T04:07:45+09:00
Subject: Re: Local variables & blocks

On Thu, 30 Jan 2003, Joel VanderWerf wrote:

> ahoward wrote:
> > wouldn't that break backward compatibility since any code like
> >
> > x = 'something completely unrelated'
> > ....
> > # 1000 lines of code
> > ....
> >
> > block_method do |arg|
> >   x = 42
> > end
> >
> > would clobber the previous x?
>
> That's how it works now, isn't it?

whoa.  to little sleep!  apologies.  that is, of course, how it works now.  i
guess i was wondering about automatically exporting every (currently local)
block variable since code which did previously :

  loop do
    ...
    object = 42
    ...
  end

  ...
    # code which may set object
  ...

  ...
    object and object.method
  ...


may act differently since object would now _always_ be defined.  it seems like
the 'new' rule will cause people to start writing

  loop do
    object = 42
  end

  object = nil

to undef objects things.  particularly with common var names like i, x, etc.

personally i like

  loop do
    export object = 42
  end

because old code will work identically, the syntax is very clear, and it
allows blocks to define variable outside their enclosing scope.

-a

-- 

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 | Ara Howard
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