I don’t think Prolog is a language in which to code entire applications, but nevertheless in some circumstances its very useful at what it does – Logic Programming, particularly rules based decision making.

The project I’m currently working on involves Prolog heavily as a back-end to carry out logical queries in a Service Oriented Architecture. The way I see it there’s many advantages to Prolog if you use it in the right circumstances: a well written piece of Prolog code can convey much more about its meaning than if the same logic were implemented in another language, and can be rapidly developed and modified as requirements change.

* The Prolog implementation we used was http://www.swi-prolog.org/

* I’m not aware of any Prolog implementations in .NET, other than the ones Matt mentioned.

* I could have developed a rule engine; but a point of this post was the money and schedule saved by not doing so.

* Of course the timing depends on the system needs. For this system, a few-minutes cycle time is amply good enough.

http://en.wikipedia.org/wiki/P_Sharp

http://homepages.inf.ed.ac.uk/stg/research/Psharp/

Hope this helps.

I developed an home automation system (EgidaLive project). Some years ago I thought that a good home automation system must manage rules. I choose .Net (I’m listening some comments… but the system functions very well!)
When you think about rules you think Prolog. I searched a .Net implementation but I didn’t succedeed to find one. I found only Mercury, but it was impossibile to use in a real system. So I developed a rule manager that takes a XML file and manages all the rules. You can imagine an infinite numbers of scenarios: “when something happens than … “. The system integrates sensors, ligths (also leds), cameras, music, flagrances, audio and video communications, …

I’d like to introduce something like a Prolog engine in order to build a smarter system. I’ve just launched a Google search and I’ve found http://sourceforge.net/projects/cs-prolog/

Is someone interested in talking about problems like these ones?

As a Prolog programmer turned SQL guy, I’ve often wanted to see both languages working together on a common problem.

It would be really nice to call Prolog directly from .NET but I’ve not seen that done.

I occasionally find problems like that, which are far easier to solve in a declarative style than anything else.

There’s been many a time when I’ve built myself a little continuation-passing micro-prolog in whatever the current-default-language happens to be since it’s easier than reformulating the problem in another way (see http://www.perlmonks.org/?node_id=193649 for a naive Prolog-in-Perl implementation for example!)