From: matz@... (Yukihiro Matsumoto)
Date: 2003-01-31T08:03:54+09:00
Subject: Re: Local variables & blocks

Hi,

In message "Re: Local variables & blocks"
    on 03/01/31, ahoward <ahoward@fsl.noaa.gov> writes:

|> Describe your feeling and ideas.
|
|please also see prior threads.

I've read "export" stuff.  But it's a matter of policy.

And I now believe scope nesting is a bad thing, at least not as good
as I expected when I introduced the current "block local variable"
behavior.  Besides, variable shadowing is evil.

So I think "export" is not the way for Ruby to go.

|> This is why I post.  What kind of situations do you think this change does
|> not cover properly?
|
|  * Threads

Incompatibility can be a problem here.  But language designers also
need a chance to fix bad design.  We are not perfect.

|  * GC

This would not be a problem except for cases like:

|  * Need to track memory usage in blocks :
|
|      (2 << 15).times do |i|
|	eval "leak_#{i} = 'a big fat leak' * (2 << 16)"
|      end

which I believe pretty exceptional.  Ruby don't stop you when you
order it to shoot your foot.  It's your responsibility.

|  * Comfort in knowing a module writer cannot fill your namespace up
|    inadvertantly

I don't really understand this namespace issue.  Could you explain
more?  Modules don't and won't pollute in-block namespace.

							matz.