From: Rick DeNatale <rick.denatale@...>
Date: 2008-01-11T06:35:38+09:00
Subject: Re: why does this code leak?

On 1/10/08, Robert Dober <robert.dober@gmail.com> wrote:

> I honestly fail to see why the closure shall take a reference to the
> object . I am with Ara here, no need to keep a reference to the object
> and this is not only MHO but also that one of Ruby1.9;), if not a bug
> at least it is odd behavior.

Because the code which creates the proc doesn't do any analysis of
what's inside the block.

It's like the story about the guy who checked out of hotel, and
protested the mini-bar charge on his bill, saying, "I didn't use
anything from the mini-bar."  The Hotel manager said,  "I'm sorry sir,
it's Hotel policy, the mini-bar was available for your use, and we
have to charge a fee to maintain it."

The man hesitated a second and quickly wrote out a bill for $100 and
presented it to the Hotel Manager, who asked "What's this for?"

The man said "For sleeping with my wife."

The Hotel manager said, "I didn't sleep with your wife!"

To which the man said, "But she was available for your use, and she's
much more expensive to maintain than that mini-bar."


Seriously, it might be possible for the Ruby parser to mark the AST or
byte-codes representing a block to indicate whether or not it needed
to be a closure or not, and perhaps even to limit what actually got
bound, but as far as I know it doesn't.

I'm also of the opinion that expecting objects to be reclaimed as
rapidly as 'logically' possible might not be the best trade-off in
designing a GC anyway.

-- 
Rick DeNatale

My blog on Ruby
http://talklikeaduck.denhaven2.com/