From: Trans <transfire@...>
Date: 2005-07-31T02:06:02+09:00
Subject: Re: make local var visible


David A. Black wrote:
>
> That would essentially do away with the notion of a local variable.  I
> think it's valuable to have them -- really quarantined "scratchpad"
> things that just don't overlap between scopes.  Writing things that
> depend on local variable names from other scopes is pretty fragile.
>

Would it? Hmm.. I guess I was thinking that if you assigned a vairable
in the current scope it would get locked into that scope, and hence be
just as local as it ever was (kind of like method vs. local var).

  foo = 1
  p foo
  def x
    foo = 2
    p foo
  end
  x
  p foo

_produces_

  1
  2
  1

To hang on to the outerscope one would have to "replace" foo instead of
assign it. Tough I suppose that'd require a general ability to use
#replace on anything (and probably a replace operator like ":=").
Nonetheless, doesn't that preserve local vars and yet "open-up" the
scopes? (Mind you I'm not neccessarily suggesting this would even be
possibile given how Ruby is implemented, but the idea in general seems
intriging.)

T.