From: Brad Tilley <rtilley@...>
Date: 2006-11-08T04:54:33+09:00
Subject: Re: Inter-thread synchronization

Quoting Caleb Clausen <vikkous@gmail.com>:

> I'm actually of two minds about whether a future ruby that supports
> native threads should still have green threads too using the existing
> Thread/Mutex/Queue/etc. Usually when making the transition from one to
> the other, you want to keep the old interface around for
> compatibility. Green threads are generally cooperative...

I thought this too. I've been using green threads in Ruby lately. They are not
that bad. Certainly, they do some things well... especially smaller things. If
it's not too difficult, having green threads available in YARV/Ruby 2.0 would
be nice. Perhaps users could choose between using the new native threads or the
old green threads. If this is too difficult, or not very feasible, that's OK. If
I could only have one, I would choose native threads.

> Finally, a fairly trivial item. It's somewhat confusing that you have
> to require 'thread' and not 'mutex' to get the Mutex class, whereas
> Thread is built-in and one doesn't need to require 'thread' to get it
> at all (if you can manage without high-level synchronization).

Isn't the same true about Queue? I found that confusing the first time I used
threads... until I discovered that I had to require 'thread' first:

irb(main):013:0> x = Queue.new
NameError: uninitialized constant Queue
        from (irb):13
        from :0
irb(main):014:0> require 'thread'
=> true
irb(main):015:0> x = Queue.new
=> #<Queue:0x606d4 @waiting=[], @que=[]>
irb(main):016:0> puts x.class
Queue
=> nil
irb(main):017:0>