1 unstable release
Uses old Rust 2015
0.1.0 | Feb 6, 2016 |
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#1312 in Math
24KB
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rslogic
rslogic is a logic programming framework for Rust inspired by µKanren.
A logical statement is built from variables, states, and goals. Create an initial state, then obtain some variables (and resulting state) from it. Construct a goal consisting of variable bindings, logical operations (AND, OR), or predicates. Then evaluate the goal using the state resulting from making the variables. Evaluating a goal returns all possible solutions to the statement, in the form of a number of states containing variable bindings.
use rslogic::state;
use rslogic::state::{Unif, State, PossibleStates};
use rslogic::goal;
use rslogic::goal::{Goal, fail, unify_val, unify_vars, conj, disj, pred};
let s = state::State::<i32>::empty();
let (v1, s) = s.make_var();
let (v2, s) = s.make_var();
let n = 123;
let g = goal::conj(goal::unify_vars(&v1, &v2), goal::unify_val(&v2, n));
let results = g.eval(&s);
assert_eq!(results.len(), 1);
let bound_value = results[0].get(&v1).unwrap();
assert_eq!(bound_value, &n);
This example creates two variables, v1
and v2
, and then assembles a logical expression
equivalent to (v1 = v2) && (v2 = 123)
. When evaluated, the resulting state binds 123
to
both v1
and v2
.