From: Yukihiro Matsumoto <matz@...>
Date: 2006-10-10T23:26:25+09:00
Subject: Re: || explanation in ruby... in pseudolanguage

Hi,

In message "Re: || explanation in ruby... in pseudolanguage"
    on Tue, 10 Oct 2006 23:16:53 +0900, ara.t.howard@noaa.gov writes:

|i know this has been discussed many times, and block locals definitely makes
|sense, but it __is__ a massive change that will break quite a bit of code.

Yes.

|is there somewhere the new scoping rules are spelled out so we can get a heads
|up?

Not yet.  I am stuck with the idea named local variable propagation,
which upgrades variable scope if it is used outside of the scope (and
within a method), i.e.

  def foo
    4.times do
      a = gets
    end
    p a  # accessing a upgrades its scope.
  end

But block parameters and explicitly declared block local variables are
not subject of this upgrading.

|is there a reccomended approach that will work in both 1.8 and 1.9 so as
|to smooth the transition?

Consider block parameters are block local even when you're using 1.8.
It's a good thing in general, I think.

							matz.