From: Hugh Sasse <hgs@...>
Date: 2005-09-28T01:41:06+09:00
Subject: Re: Rinda frustration

On Wed, 28 Sep 2005, Rick Nooner wrote:

> On Tue, Sep 27, 2005 at 10:53:02PM +0900, Hugh Sasse wrote:
>> On Tue, 27 Sep 2005, Joe Van Dyk wrote:
>>
>>> Anyone recommend a plainer-english version of some documentation that
>>> goes into Linda/Rinda basics?
>>>
>>
>> There is this:
>>
>> http://www.chadfowler.com/ruby/drb.html
>>
>> by Chad Fowler,  and I started to write
>>
>> http://www.eng.cse.dmu.ac.uk/~hgs/ruby/dRuby/
>>
>> before Druby-2.0.4 came out, so some of it is out of date, and some
>> aspects I don't understand yet anyway.  I've not had time * energy
>> to update it recently, but patches would be welcome :-)
>>
>>         HTH
>>         Hugh
>>>
>>
>
> These sites are good for an intro to dRB and I wish I would have known

Thank you.

> about them when I first started dealing with dRB, but they don't talk
> about Rinda at all.
>
> Rinda is built on top of dRB so an understanding of dRB is necessary
> before tackling Rinda, however it would be nice to have more
> documentation on Rinda itself.
>
> You do provide some good links to Linda sites.

Which I preface with
  The Linda programming paradigm is included here because of its
  applicability ro Rinda, which is part of dRuby.

But yes, that's barely a big enough mention of Rinda to be
considered "vanishingly small".
>
> Someone could ask why, with the remote object invocation capabilities
> of dRB would someone even want Rinda.  It's because Rinda provides
> a distributed "blackboard" that can simplify communication among
> many distributed processes.  We need a site that explains this
> in detail, with examples since most people have never been exposed
> to such a thing.

Also the blackboard handles concurrency issues well (using Ruby's
Threads), so that one need not concern themselves with these matters.
The blackboard, storing objects as Tuples - Arrays of things,
allows wildcard matching of objects so you can find them.  You can
search for tuples where nil is regarded as a placeholder for
anything (like .* in regexps or * in a glob).  This allows you to
query the tuplespace to see if the tuples you want are there. 
It does mean that you need to know the length of the tuple you are
looking for however.

I can't tell you much about Ring -- it seems to be a way of making
tuplespaces themselves visible to packages using it, but I don't
understand how it works yet.

>
> Rick
>
> -- 
> Rick Nooner
> rick@nooner.net
> http://www.nooner.net
>
>
>