Crate prolog2 

Prolog²

A Meta-Interpretive Learning (MIL) framework implementing native second-order SLD resolution. Prolog² extends traditional Prolog with the ability to learn logical rules from examples through predicate invention.

Library usage

The primary use case for the library is writing custom predicate modules and hooking them into the engine. The app::App builder handles configuration loading, module registration, and execution.

use std::process::ExitCode;
use std::sync::Arc;
use prolog2::app::{APP, Config};
use prolog2::predicate_modules::{
    MATHS, META_PREDICATES, PredReturn, PredicateFunction, PredicateModule,
};
use prolog2::heap::query_heap::QueryHeap;
use prolog2::program::hypothesis::Hypothesis;
use prolog2::program::predicate_table::PredicateTable;

fn my_pred(
    heap: &mut QueryHeap,
    hypothesis: &mut Hypothesis,
    goal: usize,
    pred_table: Arc<PredicateTable>,
    config: Config,
) -> PredReturn {
    // Custom predicate logic here
    PredReturn::True
}

static MY_MODULE: PredicateModule = &[
    ("my_pred", 1, my_pred),
];

fn main() -> ExitCode {
    Prolog2::from_args()
        .add_module(&MATHS)
        .add_module(&META_PREDICATES)
        .add_module(&MY_MODULE)
        .run()
}

Re-exports

pub use app::BodyClause;

pub use app::Config;

pub use app::Examples;

pub use app::SetUp;

Modules

app

Application builder and configuration types.

heap

Heap memory management: cells, query heaps, and the symbol database. Heap memory management for terms.

parser

Prolog source parsing: tokenisation, syntax tree construction, and term encoding. Prolog source parsing.

predicate_modules

Built-in predicate modules and the predicate module system.

program

Program representation: clauses, hypotheses, and the predicate table. Program representation.

resolution

Resolution engine: proof search, unification, and term building. Resolution engine.