# rslogic

**[rslogic](https://github.com/kulibali/rslogic)** is a logic programming framework
for Rust inspired by [µKanren](https://github.com/jasonhemann/microKanren).

[API Documentation](https://kulibali.github.io/rslogic)

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`.