Show HN: O'Doyle Rules – a new rules engine for Clojure • Hacker News Board

Re: Show HN: O'Doyle Rules – a new rules engine for Clojure

#11

Post by stingraycharles » Mon, Sep 14, 2020, 8:44 PM UTC

adamkl wrote: post #8

stingraycharles wrote: post #7

Earlier quoted context omitted.

Thanks for sharing, I’m ashamed to admit that I never really “got” these rule engines, but seeing this example finally made things click for me. Am I correct that there’s a very large overlap between rule engines and workflow engines, and one could use a rule engine like this to implement workflows?

I have been playing with the idea that a rule engine would work well with a state machine. State machine manages the workflow, rule engine determines which transitions to execute? Maybe that is overkill, but I've been trying to build a model in my head on how to model complex business processes.

Exactly this is what I was thinking. We currently have a workflow engine that is event driven + a projection (think: CQRS), and it’s fairly unwieldy. Most specifically, the business logic is defined all over the place, and I was wondering whether a rule engine would make it easier to define the constraints and business logic to act upon these events.

Re: Show HN: O'Doyle Rules – a new rules engine for Clojure

#12

Post by strontian » Mon, Sep 14, 2020, 9:39 PM UTC

This author is really talented and creates a lot of interesting projects. I spent some time reviewing nightcoders.net and the code quality is really impressive.

Re: Show HN: O'Doyle Rules – a new rules engine for Clojure

#13

Post by tyre » Mon, Sep 14, 2020, 9:40 PM UTC

kyleblarson wrote: post #4

I hope I'm not the only one here old enough to get the reference in the engine's name.

not at all. I'm a 90s child and found this hilarious

Re: Show HN: O'Doyle Rules – a new rules engine for Clojure

#14

Post by neovive » Mon, Sep 14, 2020, 9:41 PM UTC

kyleblarson wrote: post #4

I hope I'm not the only one here old enough to get the reference in the engine's name.

You're not alone :) Now off I go to check if Billy Madison is on Netflix.

Re: Show HN: O'Doyle Rules – a new rules engine for Clojure

#15

Post by tmh88j » Mon, Sep 14, 2020, 9:55 PM UTC

optimuspaul wrote: post #10

kyleblarson wrote: post #4

I hope I'm not the only one here old enough to get the reference in the engine's name.

I must be too old because I didn't get it.

It's from the movie Billy Madison. There was a family of bullies with the last name of O'Doyle, and everytime they picked on someone afterwards they would say "O'Doyle Rules". They eventually had an incident with a banana peel, but you'll have to watch the movie for that one ;)

Re: Show HN: O'Doyle Rules – a new rules engine for Clojure

#16

Post by jdmichal » Mon, Sep 14, 2020, 11:23 PM UTC

adamkl wrote: post #8

stingraycharles wrote: post #7

Earlier quoted context omitted.

Thanks for sharing, I’m ashamed to admit that I never really “got” these rule engines, but seeing this example finally made things click for me. Am I correct that there’s a very large overlap between rule engines and workflow engines, and one could use a rule engine like this to implement workflows?

I have been playing with the idea that a rule engine would work well with a state machine. State machine manages the workflow, rule engine determines which transitions to execute? Maybe that is overkill, but I've been trying to build a model in my head on how to model complex business processes.

Have you looked into something like BPMN + DMN? BPMN provides workflow modeling and basic decisions, and DMN provides decision tables which can implement more complex rules. There are a couple frameworks which can work on top of that to provide a system implementation.

Re: Show HN: O'Doyle Rules – a new rules engine for Clojure

#17

Post by grimgrin » Mon, Sep 14, 2020, 11:50 PM UTC

kyleblarson wrote: post #4

I hope I'm not the only one here old enough to get the reference in the engine's name.

prob the biggest reason i don't like these type of comments is that the replies will really never be interesting. there is no way for them to be, by nature of the parent not being interesting

and i'm not even shaming you, but finally creating words for my thought when i'm irritated heh

edit: by nature of the parent comment, you are able to unfold the origin of the name (and there was no reference elsewhere). ok, fine then :P

Re: Show HN: O'Doyle Rules – a new rules engine for Clojure

#18

Post by christophilus » Tue, Sep 15, 2020, 1:49 AM UTC

strontian wrote: post #12

This author is really talented and creates a lot of interesting projects. I spent some time reviewing nightcoders.net and the code quality is really impressive.

That link is broken. I think you meant this: https://github.com/oakes/Nightcoders

And that is now a read only project. So, I guess it’s defunct.

Re: Show HN: O'Doyle Rules – a new rules engine for Clojure

#19

Post by [deleted] » Tue, Sep 15, 2020, 2:21 AM UTC

[deleted]

Re: Show HN: O'Doyle Rules – a new rules engine for Clojure

#20

Post by [deleted] » Tue, Sep 15, 2020, 2:22 AM UTC

tmh88j wrote: post #15

optimuspaul wrote: post #10

Earlier quoted context omitted.

I must be too old because I didn't get it.

It's from the movie Billy Madison. There was a family of bullies with the last name of O'Doyle, and everytime they picked on someone afterwards they would say "O'Doyle Rules". They eventually had an incident with a banana peel, but you'll have to watch the movie for that one ;)

[deleted]