Mark, in my talk at RulesFest 2011 I've demonstrated that DSLs in their current form are indeed useful, perhaps not quite as easy to use as marketing hype promises. The current DSL process exploits regular expressions in a clever way, but this has limits. (Programming in something close to natural language has been an ongoing dream since Rear Admiral G. Hopper's fine achievement, but no remarkable progress has been made in half a century.) I have presented DSL rules more than once to an audience, and it seems that getting non-geeks to appreciate rules is made easier this way. There is nothing in the current DSL that depends on DRL except the undisputed keywords delimiting a rule. I can see no reason why DSL shouldn't just stay the way it is: the documentation is fairly complete (much more than for some other Expert features) and it hasn't needed many bugfixes I'm aware of. Cheers Wolfgang On 29/01/2013, Mark Proctor <mproctor(a)codehaus.org&gt; wrote: > How would people feel if we removed DSLs from 6.0? There is no decision > either way, but I wanted to see if people liked or disliked the idea. > > My reason for this is I don't believe DSLs in their current form, beyond > demo ware, are useful. They need a lot more work to turn them into guided > structured documents, we don't have the people to focus on that right now, > and no one from the community has taken this on. > > I'd rather see them removed, until they can be done properly. > > Mark > _______________________________________________ > 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

Btw the other reasons it comes up is tooling, in guvnor. People want to be able to change their DSLs, and have the guided editors updated to reflect this, without having to update each DSL manually. And then their is the request for nested, scoped and related DSL fragments. Mark On 29 Jan 2013, at 05:43, Mark Proctor <mproctor(a)codehaus.org&gt; wrote: > One of the reasons this came up was due to round tripping from the guided > editor to drl text format. This is so the guided editor does not use it's > own proprietary xml format, but instead uses the .drl directly. > > Round tripping DRL is not so hard. Round tripping DSLs is much harder, and > I suspect will be hard to get fool proof regex. Also we would at a minimum > require an escape in the DRL to delimit a DSL sentence. > > If you think DSLs are useful, I think we can leave them in, with the > caveat of the escape. Sound ok? > > Mark > On 29 Jan 2013, at 05:30, Wolfgang Laun <wolfgang.laun(a)gmail.com&gt; wrote: > >> Mark, >> >> in my talk at RulesFest 2011 I've demonstrated that DSLs in their >> current form are >> indeed useful, perhaps not quite as easy to use as marketing hype >> promises. The current DSL process exploits regular expressions in a >> clever way, but this has limits. (Programming in something close to >> natural language has been an ongoing >> dream since Rear Admiral G. Hopper's fine achievement, but no >> remarkable progress has been made in half a century.) >> >> I have presented DSL rules more than once to an audience, and it seems >> that getting non-geeks to appreciate rules is made easier this way. >> >> There is nothing in the current DSL that depends on DRL except the >> undisputed keywords delimiting a rule. I can see no reason why DSL >> shouldn't just stay the way it is: the documentation is fairly complete >> (much >> more than for some other Expert features) and it hasn't needed many >> bugfixes I'm aware of. >> >> Cheers >> Wolfgang >> >> On 29/01/2013, Mark Proctor <mproctor(a)codehaus.org&gt; wrote: >>> How would people feel if we removed DSLs from 6.0? There is no decision >>> either way, but I wanted to see if people liked or disliked the idea. >>> >>> My reason for this is I don't believe DSLs in their current form, >>> beyond >>> demo ware, are useful. They need a lot more work to turn them into >>> guided >>> structured documents, we don't have the people to focus on that right >>> now, >>> and no one from the community has taken this on. >>> >>> I'd rather see them removed, until they can be done properly. >>> >>> Mark >>> _______________________________________________ >>> 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 list rules-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-dev

How would people feel if we removed DSLs from 6.0? There is no decision either way, but I wanted to see if people liked or disliked the idea. My reason for this is I don't believe DSLs in their current form, beyond demo ware, are useful. They need a lot more work to turn them into guided structured documents, we don't have the people to focus on that right now, and no one from the community has taken this on. I'd rather see them removed, until they can be done properly. Mark _______________________________________________ rules-dev mailing list rules-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-dev

Drools has been backwards compatible since 2006. We'll provide migration paths, but we cannot guarantee backwards computability indefinitely. For instance in the case of DSLs, if we were to drop them, we could provide a migrate script that rendered them all to pure drl (without any remaining DSL) so that they would continue to be executable. Mark On 29 Jan 2013, at 06:33, Ansgar Konermann < ansgar.konermann(a)googlemail.com&gt; wrote: I value source code compatibility much higher than a guided editor. We do all out rules editing in a plain text editor. But we absolutely need the certainty that we can compile and run our existing mortgage scoring rules for our mission-critical system with the next major version of drools. After all, rules also are what they are termed in Guvnor: assets. Please protect my assets. Thanks Ansgar Am 29.01.2013 00:08 schrieb "Mark Proctor" <mproctor(a)codehaus.org&gt;: > How would people feel if we removed DSLs from 6.0? There is no decision > either way, but I wanted to see if people liked or disliked the idea. > > My reason for this is I don't believe DSLs in their current form, beyond > demo ware, are useful. They need a lot more work to turn them into guided > structured documents, we don't have the people to focus on that right now, > and no one from the community has taken this on. > > I'd rather see them removed, until they can be done properly. > > Mark > _______________________________________________ > 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 list rules-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-dev

Hi all, after a (quite long) discussion with Mark, Edson and Michael we realized that, to support the guided editor roundtrip without dropping our current DSL features, we need a new format allowing to mix plain DRL and DSL sentences but delimiting these last ones in a clear (and easy to recognize) way. Our first idea has been to not have dsl blocks and mark each dsl line with an initial single quote (') like in

For the same reason we could have similar problems with many other (not too fancy) characters. Moreover it happens quite often to have a dsl that spans more lines, especially considering the - notation already remembered by Wolfgang in a former email of this thread.

Taking count of that, I suggest to adopt a (xml-like) syntax that is a bit more verbose but also much more explicit and less error-prone, like in the following example that mixes plain drl with dsl parts:

Moreover I'd prefer to have a specific file extension for this kind of rule files instead of using the standard .drl one.

I can't think to nothing better than .edrl (standing for Enriched DRL) at the moment, so I am open to any suggestion.

Any other feedback is welcome, Mario