Hi Mario, that document looks great.. I will take some time to read it and I will try to give some feedback. I was playing with cypher (from neo4j, a graph oriented DB) (total newbie on that) but looking at your in line acc functions I think that we can take some concepts from cypher and apply them in DRL. Cheers On Wed, Oct 19, 2011 at 5:59 PM, Mario Fusco <mario.fusco(a)gmail.com <mailto:mario.fusco@gmail.com>> wrote: Hi all, as anticipated by Mark, I put down some ideas on how we could start introducing some functional programming features in the DRL. http://community.jboss.org/wiki/FunctionalProgrammingInDrools It's needless to say that the document has to been considered just a draft in its very first stage and any feedback or suggestion to improve or clarify it is welcome. Mario _______________________________________________ rules-dev mailing list rules-dev(a)lists.jboss.org <mailto:rules-dev@lists.jboss.org> https://lists.jboss.org/mailman/listinfo/rules-dev -- - CTO @ http://www.plugtree.com - MyJourney @ http://salaboy.wordpress.com - Co-Founder @ http://www.jugargentina.org - Co-Founder @ http://www.jbug.com.ar - Salatino "Salaboy" Mauricio - _______________________________________________ rules-dev mailing list rules-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-dev

I would also like to keep it as close to Java as possible. There are few problems here: * It could never go beyond Java * We are using Java 5 and just considering Java 6, this would be a huge leap :-) But then again if we don't use the Java way, then what will we do when Drools reaches Java 8, support both? Toni On Oct 20, 2011, at 11:08 AM, Geoffrey De Smet wrote: Interesting stuff. This is basically "closures" which will be available in JDK 8 + LHS closure pattern support 1) About "closures" which will be available in JDK 8: Since functions contain Java code, which is imperative, not declarative, I don't consider that DRL turf any more. *Our closure syntax should there should be exactly the same as Java 8.* Here's their syntax, which looks the same on first sight, but the devil is in the details (= unreleased spec): http://mail.openjdk.java.net/pipermail/lambda-dev/2011-September/003936.html Either we wait for JDK 8 to be released to support closures (current release date is 2012 according to Mark R.'s "plan B" that released JDK 7 in 2011) or we implement it just like the JDK8 with the exact same syntax (which is a LOT of work). 2) About LHS closure pattern support. This builds on top of 1) to allow usage of closures in the LHS. Cool stuff, I like the piping idea. Op 19-10-11 23:12, Mauricio Salatino schreef: Hi Mario, that document looks great.. I will take some time to read it and I will try to give some feedback. I was playing with cypher (from neo4j, a graph oriented DB) (total newbie on that) but looking at your in line acc functions I think that we can take some concepts from cypher and apply them in DRL. Cheers On Wed, Oct 19, 2011 at 5:59 PM, Mario Fusco <mario.fusco(a)gmail.com&gt;wrote: > Hi all, > > as anticipated by Mark, I put down some ideas on how we could start > introducing some functional programming features in the DRL. > > http://community.jboss.org/wiki/FunctionalProgrammingInDrools > > It's needless to say that the document has to been considered just a draft > in its very first stage and any feedback or suggestion to improve or clarify > it is welcome. > > Mario > > _______________________________________________ > rules-dev mailing list > rules-dev(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-dev > > -- - CTO @ http://www.plugtree.com - MyJourney @ http://salaboy.wordpress.com - Co-Founder @ http://www.jugargentina.org - Co-Founder @ http://www.jbug.com.ar - Salatino "Salaboy" Mauricio - _______________________________________________ rules-dev mailing listrules-dev@lists.jboss.orghttps://lists.jboss.org/mailman/listinfo/rules-dev -- With kind regards, Geoffrey De Smet _______________________________________________ rules-dev mailing list rules-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-dev _______________________________________________ rules-dev mailing list rules-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-dev

** The minimum java version we require (currently java 5) need not be the same as the maximum java version language features we support. For example, drools 6 could require at least java 5 to run, but - if source>=7 and target>=7 you can use switch(String) and other coin stuff in DRL functions - if source>=8 and target>=8 you can use closures in DRL functions The point is... drools-core source code itself can't use that stuff (unless it's in the extension module drools-core-jdk7). Spring 2.0.0 did something similar IIRC: it required at least JDK 1.4, but if it detected JDK 1.5 you could use annotations too. Note: despite all that, I still wish we move the minimum java version to 6 :) Op 20-10-11 13:26, Wolfgang Laun schreef: Last time Mark asked, there was a huge outcry - some people using some Java that's standing still at Java 5. -W On 20 October 2011 13:21, Toni Rikkola <toni.rikkola(a)gmail.com&gt; wrote: > I would also like to keep it as close to Java as possible. > > There are few problems here: > * It could never go beyond Java > * We are using Java 5 and just considering Java 6, this would be a huge > leap :-) > > But then again if we don't use the Java way, then what will we do when > Drools reaches Java 8, support both? > > Toni > > On Oct 20, 2011, at 11:08 AM, Geoffrey De Smet wrote: > > Interesting stuff. > This is basically > "closures" which will be available in JDK 8 > + LHS closure pattern support > > 1) About "closures" which will be available in JDK 8: > Since functions contain Java code, which is imperative, not declarative, I > don't consider that DRL turf any more. > *Our closure syntax should there should be exactly the same as Java 8.* > Here's their syntax, which looks the same on first sight, but the devil is > in the details (= unreleased spec): > > http://mail.openjdk.java.net/pipermail/lambda-dev/2011-September/003936.html > Either we wait for JDK 8 to be released to support closures (current > release date is 2012 according to Mark R.'s "plan B" that released JDK 7 in > 2011) > or we implement it just like the JDK8 with the exact same syntax (which is > a LOT of work). > > 2) About LHS closure pattern support. > This builds on top of 1) to allow usage of closures in the LHS. > Cool stuff, I like the piping idea. > > Op 19-10-11 23:12, Mauricio Salatino schreef: > > Hi Mario, that document looks great.. I will take some time to read it and > I will try to give some feedback. > I was playing with cypher (from neo4j, a graph oriented DB) (total newbie > on that) but looking at your in line acc functions I think that we can take > some concepts from cypher and apply them in DRL. > Cheers > > On Wed, Oct 19, 2011 at 5:59 PM, Mario Fusco <mario.fusco(a)gmail.com&gt;wrote: > >> Hi all, >> >> as anticipated by Mark, I put down some ideas on how we could start >> introducing some functional programming features in the DRL. >> >> http://community.jboss.org/wiki/FunctionalProgrammingInDrools >> >> It's needless to say that the document has to been considered just a >> draft in its very first stage and any feedback or suggestion to improve or >> clarify it is welcome. >> >> Mario >> >> _______________________________________________ >> rules-dev mailing list >> rules-dev(a)lists.jboss.org >> https://lists.jboss.org/mailman/listinfo/rules-dev >> >> > > > -- > - CTO @ http://www.plugtree.com > - MyJourney @ http://salaboy.wordpress.com > - Co-Founder @ http://www.jugargentina.org > - Co-Founder @ http://www.jbug.com.ar > > - Salatino "Salaboy" Mauricio - > > > _______________________________________________ > rules-dev mailing listrules-dev@lists.jboss.orghttps://lists.jboss.org/mailman/listinfo/rules-dev > > > -- > With kind regards, > Geoffrey De Smet > > _______________________________________________ > rules-dev mailing list > rules-dev(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-dev > > > > _______________________________________________ > rules-dev mailing list > rules-dev(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-dev > > _______________________________________________ rules-dev mailing listrules-dev@lists.jboss.orghttps://lists.jboss.org/mailman/listinfo/rules-dev -- With kind regards, Geoffrey De Smet _______________________________________________ rules-dev mailing list rules-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-dev

Hi all, as anticipated by Mark, I put down some ideas on how we could start introducing some functional programming features in the DRL. http://community.jboss.org/wiki/FunctionalProgrammingInDrools It's needless to say that the document has to been considered just a draft in its very first stage and any feedback or suggestion to improve or clarify it is welcome. Mario _______________________________________________ rules-dev mailing list rules-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-dev

On 20 October 2011 13:15, Toni Rikkola <toni.rikkola(a)gmail.com&gt; wrote: I'm just asking if we can drop the brackets and maybe even the commas to get a cleaner look. Do you mean parentheses, i.e. ()? How will a parser be able to determine the end of a parameterlist if there is one call inside the other? -W _______________________________________________ rules-dev mailing list rules-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-dev

Yes parentheses. And I don't know the answer to the next question, just asking because I have seen it work in other languages :-) Not a must have, in other cases using parentheses is cleaner.

Toni On Oct 20, 2011, at 2:25 PM, Wolfgang Laun wrote: > > > On 20 October 2011 13:15, Toni Rikkola <toni.rikkola(a)gmail.com > <mailto:toni.rikkola@gmail.com>> wrote: > > I'm just asking if we can drop the brackets and maybe even the > commas to get a cleaner look. > > > Do you mean parentheses, i.e. ()? > > How will a parser be able to determine the end of a parameterlist if > there is one call inside the other? > > -W > _______________________________________________ > rules-dev mailing list > rules-dev(a)lists.jboss.org <mailto:rules-dev@lists.jboss.org> > https://lists.jboss.org/mailman/listinfo/rules-dev _______________________________________________ rules-dev mailing list rules-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-dev

Toni, correct me if I'm wrong: your suggestion looks very similar to what you do in Haskell where the syntax without parenthesis and commas is allowed by the fact that in this language every function officially takes only one parameter, while the functions that apparently accept more than one argument are actually curried functions. You can find more explanations about this syntax, for example, here: http://learnyouahaskell.com/higher-order-functions Despite I like this syntax because it allows to eliminate some punctuation making the code often (but not always) more readable I also see 2 main problems with it: 1. It implies a larger use of curried functions and I am not sure that the biggest part of Drools users will feel comfortable with them. 2. It will bring our syntax even farther from the one that will be available in Java 8.