kyouko-taiga/logickit

A Prolog-like language as a Swift Embedded Domain Specific Language.

Hi there 👋

My name is Dimi Racordon. I love coding stuff, talking about programming languages and playing Stracraft 2.

I am a researcher focusing my work on type-based approaches for memory safety. My main research interests include type systems (obviously), language design, compiler construction and virtual machine implementations. I am currently directing most of my efforts in a project called Hylo with the objective to explore the use of mutable value semantics to create a safe-by-default and fast-by-definition programming language for generic high-level systems programming.

logickit's Issues

Merging two knowledge bases with `+` doesn't work

Merging two knowledge bases with + doesn't produce correct results.

Arithmetic comparisons

Is there a way to get results that satisfy arithmetic comparisons? e.g.
kb.ask (.fact("number of children", var("x"), var("y")>3)

I suspect that built functions have this ability but I cannot find out a way to implement it.

Thanks.

Method to count the number of terms within a rule stage

Hi I am trying to build a term that returns true if the number of results is above a specific number:

let success = Term.rule("success") {
.fact("action", "s93663", .var("date"), .var("number1"), .var("number2"))
&& List.count(list: (List.from(elements: .var("date")) , count: .var("count"))
&& Nat.greaterOrEqual( .var("count") , Nat.from(3))
}

I want to be able to count the instances of "date" in my set.

I know that it would be possible to count the items in the answerset in swift but I want to reuse the rule in other rules and I would like to be able to solve with LogicKit only.

Arm compilation

Is there a way to get LogicKit to compile for Arm?
I get:
Could not find module 'LogicKit' for target 'arm64-apple-macos'; found: x86_64, x86_64-apple-macos

Concurrency issue

Hi. LogicKit causes a Vapor server to hang. Does your code support concurrency?

[Question] Syntax help

I'm new to Prolog and i'm trying to convert some statements from an existing script using LogicKit.

This rule definition works in SWI-Prolog
inference(inheritance(M, P), inheritance(S, M), inheritance(S, P)) :- S \= P.
And when ask the system a question
inference(inheritance(bird, animal), inheritance(robin, bird), T).
It correctly responds with
T = inheritance(robin,animal)

I've tried a few different combinations but couldn't get even this simple case to work in LogicKit. As i said, I'm really new to Prolog so I must be missing something here. For one, I don't know how to express S \= P in LogicKit which I suspect is why I can't get it to work. It should be something like not ( Term.var("S") ~=~ Term.var("P") ) but I couldn't figure out how to express this.

Thanks!

This is what I have so far

let kb: KnowledgeBase = [
        .rule("inference", 
            .fact("inheritance", "M", "P"),
            .fact("inheritance", "S", "M"),
            .fact("inheritance", "S", "P")) { 
                  //
                  // what should go here???
                  //
            }
    ]
    
    let results = 
          kb.ask(
            .fact("inference", 
                .fact("inheritance", "bird", "animal"),
                .fact("inheritance", "robin", "bird"),
                .var("result"))
        )

    print(results)

Is it possible to merge several knowledge bases in a new one?

This seems to be useful for modularity.

Parsey's parser is deprecated

Parsey is deprecated, and therefore a new parser for lki should be implemented.