[][src]Function canrun_basic::cmp::lt

pub fn lt<'a, A, AV, B, BV, D>(a: AV, b: BV) -> Goal<'a, D> where
    A: PartialOrd<B> + Debug + 'a,
    B: Debug + 'a,
    AV: IntoVal<A>,
    BV: IntoVal<B>,
    D: DomainType<'a, A> + DomainType<'a, B>, 

Ensure that one value is less than another.

Example:

use canrun::{unify, util, var, all, Goal};
use canrun::domains::example::I32;
use canrun_basic::lt;

let (x, y) = (var(), var());
let goal: Goal<I32> = all![
    unify(x, 1),
    unify(y, 2),
    lt(x, y)
];
let results: Vec<_> = goal.query((x, y)).collect();
assert_eq!(results, vec![(1, 2)]);