Module programinduction::lambda

(representation) Polymorphically-typed lambda calculus.

Examples

use programinduction::lambda::{task_by_evaluation, Language, SimpleEvaluator};

fn evaluate(name: &str, inps: &[i32]) -> Result<i32, ()> {
    match name {
        "0" => Ok(0),
        "1" => Ok(1),
        "+" => Ok(inps[0] + inps[1]),
        _ => unreachable!(),
    }
}

let dsl = Language::uniform(vec![
    ("0", ptp!(int)),
    ("1", ptp!(int)),
    ("+", ptp!(@arrow[tp!(int), tp!(int), tp!(int)])),
]);

// task: sum 1 with two numbers
let tp = ptp!(@arrow[tp!(int), tp!(int), tp!(int)]);
let examples = vec![(vec![2, 5], 8), (vec![1, 2], 4)];
let task = task_by_evaluation(SimpleEvaluator::of(evaluate), tp, &examples);

// solution:
let expr = dsl.parse("(λ (+ (+ 1 $0)))").unwrap();
assert!((task.oracle)(&dsl, &expr).is_finite())

Structs

CompressionParams	Parameters for grammar induction.
Language	(representation) A Language is a registry for primitive and invented expressions in a polymorphically-typed lambda calculus with corresponding production log-probabilities.
LiftedFunction	A function object for evaluation in domains with first-class functions.
LiftedLazyFunction	Like LiftedFunction, but for lazy evaluation with a LazyEvaluator.
ParseError
SimpleEvaluator	An Evaluator defined solely by a function.

Enums

Expression	Expressions of lambda calculus, which only make sense with an accompanying Language.
InferenceError

Traits

Evaluator	A specification for evaluating lambda calculus expressions in a domain.
LazyEvaluator	Like Evaluator, but you get to decide whether certain arguments should be evaluated.

Functions

task_by_evaluation	Create a task based on evaluating lambda calculus expressions on test input/output pairs.
task_by_lazy_evaluation	Liky task_by_evaluation, but for use with a LazyEvaluator.