The inference collection (<a href="http://planet.racket-lang.org/display.ss?package=inference.plt&owner=williams">http://planet.racket-lang.org/display.ss?package=inference.plt&owner=williams</a>) in PlaneT is a hybrid forward and backward chaining inference engine that is written entirely in Racket. It uses a (rete-like) rule network internally. We have used it internally for several projects. The documentation and examples are still a bit weak - which is, of course, my fault - but I'd be happy to help others learn it.<div> <br></div><div>Doug<br><br><div class="gmail_quote">On Wed, Jan 9, 2013 at 8:48 AM, Ray Racine <span dir="ltr"><<a href="mailto:ray.racine@gmail.com" target="_blank">ray.racine@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> <div dir="ltr">Sorry off topic, but Forward Production Rete Rules Engines, such fond memories. An exact blueprint to code one from scratch is below. Jess is license encumbered, Drools is not, but I expect you've already run across it.<div> <br></div><div>And many, many moons long gone, I did an impl in SML that compiled under MLton which was PDQ. Then a buddy of mine with some assistance did what is AFAIK still the only mult-threaded / concurrent implementation (in Java) of a Reta alpha/beta network using a sort of "zipper" algo on the network graph. It's still out there <a href="http://www.zilonis.org/" target="_blank">http://www.zilonis.org/</a> , not used by anyone AFAIK, though we believe a few folks did take the code internally. We had it in production for awhile long ago (ad targeting on web). Rumor was Forgy also built a concurrent solution, but you had to model the Rete in a DSL and it compiled to Java code. Never caught on.</div> <div><br></div><div>Oh and yes of course, the Zilonis version has a "tiny" scheme interpreter built in to write capable of simple calculations, regex matches etc in the rules.<br><div><h2 style="font-weight:normal;margin:30px 0px 10px 10px;font-size:1.1em;padding:5px 0px 5px 8px;background-image:url();background-color:rgb(238,238,238);border-width:1px;border-style:solid;border-color:rgb(221,221,221) rgb(187,187,187) rgb(187,187,187) rgb(221,221,221);font-family:tahoma,verdana,sans-serif;background-repeat:repeat no-repeat"> <a href="http://docs.codehaus.org/download/attachments/8082/CMU-CS-95-113.pdf?version=1&modificationDate=1092858118000" style="text-decoration:none;color:rgb(34,102,204)" target="_blank">Production Matching for Large Learning Systems (Rete/UL)</a> <br> <br>by Robert B. Doorenbos </h2></div></div></div><div class="gmail_extra"><br><br><div class="gmail_quote"><div><div class="h5">On Wed, Jan 9, 2013 at 8:36 AM, Grant Rettke <span dir="ltr"><<a href="mailto:grettke@acm.org" target="_blank">grettke@acm.org</a>></span> wrote:<br> </div></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><div class="h5">Hi,<div><br></div><div>I have the goal of inserting some Jess (<a href="http://herzberg.ca.sandia.gov/" target="_blank">http://herzberg.ca.sandia.gov/</a>) code inside of a Scribble interaction environment (eventually I will have a language to evaluate this but I'm not there yet). Here is the relevant part of the code I have to do that:</div> <div><br></div><div><div>#lang racket</div><div><br></div><div>(define (my-read-syntax src in)</div><div> (define path-ls (get-path in))</div><div> (define path (list->string path-ls))</div><div> (define fis (open-input-file #:mode 'text path))</div> <div> (define datums (let loop ()</div><div> (let* ((datum (read fis)))</div><div> (cond ((eof-object? datum) empty)</div><div> (else (cons datum (loop)))))))</div> <div> (close-input-port fis)</div><div> (datum->syntax #f datums))</div><div><br></div><div>This does load the file and insert it into Scribble eg:</div><div><br></div><div><div>(interaction</div><div> #:eval</div> <div> my-evaluator</div><div> ((watch all)</div><div> (reset)</div><div> (defrule do-anything "A rule for anything." ?ne <- (anything) => (printout t "Someone did something.") (retract ?ne))</div> <div> (assert (anything))</div><div> (run)))))</div></div><div><br></div><div>There are two things I'm still not doing correctly though:</div><div><br></div><div>#1. I've collected the contents of that file into a list of datums that looks like this in DrRacket's console:</div> <div><br></div><div><div>'((watch all)</div><div> (reset)</div><div> (defrule</div><div> do-anything</div><div> "A rule for anything."</div><div> ?ne</div><div> <-</div><div> (anything)</div> <div> =></div><div> (printout t "Someone did something.")</div><div> (retract ?ne))</div><div> (assert (anything))</div><div> (run))</div></div><div><br></div><div>I don't want those inserted as a list though, I only want the contents inserted. Up above I see why it is happening, but I am not successfully splicing it in my attempts. What is the right way?</div> <div><br></div><div>#2. The code body is formatted at least in the output in DrRacket. When it is inserted into the Scribble environment, though, it loses some of it's formatting namely the defrule and right arrow appear in the same line. That said, when Scribble renders it, all of the code is rendered on the same line like this:</div> <div><br></div><div><table cellspacing="0"><tbody><tr><td><span>> </span><span>(</span><span>(</span><span>watch</span><span>all</span><span>)</span><span>(</span><span>reset</span><span>)</span><span>(</span><span>defrule</span><span>do-anything</span><span>"A rule for anything."</span><span>?ne</span><span><-</span><span>(</span><span>anything</span><span>)</span><span>=></span><span>(</span><span>printout</span><span>t</span><span>"Someone did something."</span><span>)</span><span>(</span><span>retract</span><span>?ne</span><span>)</span><span>)</span><span>(</span><span>assert</span><span>(</span><span>anything</span><span>)</span><span>)</span><span>(</span><span>run</span><span>)</span><span>)</span></td> </tr><tr><td><p><span>=>: arrow not allowed as an expression</span></p><p>How may I read in that file and then generated a syntax object that retains the indentation and new lines?</p><p>#3. Am I generally going about this in an OK manner? My next part of the plan to make a simple language whose only purpose in life is to evaluate Jess code and print out the results; I want to be able to use Scribble for any other Lispy language out there at least the interaction environment.</p> </td></tr></tbody></table></div> </div> <br></div></div>____________________<br> Racket Users list:<br> <a href="http://lists.racket-lang.org/users" target="_blank">http://lists.racket-lang.org/users</a><br> <br></blockquote></div><br></div> <br>____________________<br> Racket Users list:<br> <a href="http://lists.racket-lang.org/users" target="_blank">http://lists.racket-lang.org/users</a><br> <br></blockquote></div><br></div>