Extending C with Prolog (1994) (opens in new tab)

(amzi.com)

72 pointsAntibabelic1mo ago26 comments

26 comments

I started using Prolog in my self written home automation system over 20 years ago. At first I was using CORBA and I linked ACE/Tao into SWI-Prolog so that Prolog could catch and send CORBA messages. That worked for years but was too annoying to add new message types since a wrapper had to be written for each, plus threading had to be coordinated between C++ and Prolog. Eventually I ditched the CORBA stuff and switched to MQTT, but instead of binding the C++ and Prolog together I found and extended MQTT support for Prolog directly, actually I've mostly replaced the C++ parts of my HA system with Java. The Prolog is pretty nice the way I can now specify predicates for MQTT topic paths, and I use shared topics for scalability. Now all of this is running deployed in k3s.

justinhj29d ago

This sounds really cool and I am glad that Prolog has outlived CORBA

sprior29d ago

Yeah, CORBA really needed to go away.

pjmlp29d ago

Except that CORBA spirit thrives in 2026 still, gRPC, D-BUS, COM/DCOM, WinRT, XPC, Android IPC, SDKs over REST/GraphQL, MCP,...

vintagedave1mo ago

> We recently installed Gateway multi-media kits on our PCs, but found the installation less than trivial because of conflicts in our interrupt (IRQ) channels. A simple expert system could have helped to resolve those IRQ conflicts. ... The sample program is set up to allow installation of two different devices, a 'Sound Blaster' and a 'Mitsumi CD- ROM'.

This was a real blast from the past. I wonder why more systems today don't have this kind of logic solving built in. Possibly, too many complex behaviours that are not cleanly quantified.

bitwize29d ago

Pepperidge Farm remembers when reasoning systems could actually reason, instead of backing out the part of the context they're told is erroneous, appending "Wait..." and then continuing to predict tokens as before.

krzyk29d ago

Is this the time of year when we try to force redditors to stay away by posting about Prolog?

I see three stories already.

Davidbrcz29d ago

Refreshing stories between all the AI ones (and crypto/web3 before that)

linguae29d ago

Ironically, once upon a time Prolog and logic programming in general were part of the cutting-edge of AI. There's quite a fascinating history of Japan's fifth-generation computing efforts in the 1980s when Japan focused on logic programming and massively parallel computing. My former manager, who is from Japan, earned his PhD in the 1990s in a topic related to constraint logic programming.

2 more replies

thesz29d ago

You said AI: https://github.com/stassa/louise

  Louise (Patsantzis & Muggleton 2021) is a machine learning system that learns Prolog programs.

  Louise is a Meta-Interpretive Learning (MIL) system. MIL (Muggleton et al. 2014), (Muggleton et al. 2015), is a new setting for Inductive Logic Programming (ILP) (Muggleton, 1991). ILP is a form of weakly-supervised machine learning of logic programs from examples of program behaviour (meaning examples of the inputs and outputs of the programs to be learned). Unlike conventional, statistical machine learning algorithms, ILP approaches do not need to see examples of programs to learn new programs and instead rely on background knowledge, a library of pre-existing logic programs that they reuse to compose new programs.

This is what was done by Douglas Lenat from late 1970-s on [1]. He did his work using Lisp, this thing does something close using Prolog.

[1] https://en.wikipedia.org/wiki/Eurisko

1 more reply

rramadass29d ago

We need more.

In case you weren't aware, people are using Prolog with LLMs;

https://news.ycombinator.com/item?id=42039527

https://news.ycombinator.com/item?id=45712934

dgxyz29d ago

Well at least it's not clojure or scheme.

AntibabelicOP29d ago

What's the third one? I see this one and the Lambda Prolog one.

ofrzeta29d ago

Related: Using Prolog in Windows NT Network Configuration (1996) https://news.ycombinator.com/item?id=36821871

HexDecOctBin29d ago

I often wonder what a Prolog implemented as an Objective-C like extension to C would look like. Since WAM has proper stack and heap IIRC, it might be possible to plug that in through some region-based memory management on C side. Is there some prior art like this?

NetMageSCW29d ago

I ported from Pascal to C a Lisp interpreter system that had an embedded Prolog in it (that used Lisp syntax) (and wrote a new memory subsystem) in my spare time in College. Later I helped a grad student a little bit with their implementation of a Warren machine (runtime for a Prolog compiler) for it. That’s the only embedded Prolog I’m aware of.

anthk29d ago

Check http://t3x.org, it has some book on logic for Scheme which implements a Prolog under it wich very few files and lines per file.

mcswell29d ago

FWIW (not much), around the time of that article, I reversed this: I used Arity Prolog for a morphological parsing program, with C calls for the bit fiddling (because I needed 64 bits, and the Prolog I was using only handled 16 bit strings).

juancn28d ago

Windows NT used to have the network configuration run in prolog:

https://web.archive.org/web/20030218034509/http://www.resear...

crustycoder29d ago

Things have moved on since 1994, not only can you still embed it in C and a load of other languages, you can even run it directly in your browser as there's a WASM port.

https://www.swi-prolog.org/pldoc/man?section=wasm-version

buescher29d ago

There's another updated version of that prolog here along with some links, including an archived article from Microsoft Research on how it was (once upon a time) used in Windows NT network configuration: https://github.com/opless/small-prolog

j / k navigate · click thread line to collapse

26 comments

sprior29d ago

justinhj29d ago

This sounds really cool and I am glad that Prolog has outlived CORBA

sprior29d ago

Yeah, CORBA really needed to go away.

pjmlp29d ago

Except that CORBA spirit thrives in 2026 still, gRPC, D-BUS, COM/DCOM, WinRT, XPC, Android IPC, SDKs over REST/GraphQL, MCP,...

vintagedave1mo ago

This was a real blast from the past. I wonder why more systems today don't have this kind of logic solving built in. Possibly, too many complex behaviours that are not cleanly quantified.

bitwize29d ago

krzyk29d ago

Is this the time of year when we try to force redditors to stay away by posting about Prolog?

I see three stories already.

Davidbrcz29d ago

Refreshing stories between all the AI ones (and crypto/web3 before that)

linguae29d ago

2 more replies

thesz29d ago

You said AI: https://github.com/stassa/louise

  Louise (Patsantzis & Muggleton 2021) is a machine learning system that learns Prolog programs.

  Louise is a Meta-Interpretive Learning (MIL) system. MIL (Muggleton et al. 2014), (Muggleton et al. 2015), is a new setting for Inductive Logic Programming (ILP) (Muggleton, 1991). ILP is a form of weakly-supervised machine learning of logic programs from examples of program behaviour (meaning examples of the inputs and outputs of the programs to be learned). Unlike conventional, statistical machine learning algorithms, ILP approaches do not need to see examples of programs to learn new programs and instead rely on background knowledge, a library of pre-existing logic programs that they reuse to compose new programs.

This is what was done by Douglas Lenat from late 1970-s on [1]. He did his work using Lisp, this thing does something close using Prolog.

[1] https://en.wikipedia.org/wiki/Eurisko

1 more reply

rramadass29d ago

We need more.

In case you weren't aware, people are using Prolog with LLMs;

https://news.ycombinator.com/item?id=42039527

https://news.ycombinator.com/item?id=45712934

dgxyz29d ago

Well at least it's not clojure or scheme.

AntibabelicOP29d ago

What's the third one? I see this one and the Lambda Prolog one.

ofrzeta29d ago

Related: Using Prolog in Windows NT Network Configuration (1996) https://news.ycombinator.com/item?id=36821871

HexDecOctBin29d ago

NetMageSCW29d ago

anthk29d ago

Check http://t3x.org, it has some book on logic for Scheme which implements a Prolog under it wich very few files and lines per file.

mcswell29d ago

juancn28d ago

Windows NT used to have the network configuration run in prolog:

https://web.archive.org/web/20030218034509/http://www.resear...

crustycoder29d ago

Things have moved on since 1994, not only can you still embed it in C and a load of other languages, you can even run it directly in your browser as there's a WASM port.

https://www.swi-prolog.org/pldoc/man?section=wasm-version

buescher29d ago

j / k navigate · click thread line to collapse