error-message.txt

error[E0308]: mismatched types
   --> src/main.rs:12:48
    |
 12 |     let mut goal = bind(("x", "y", "z"), move |(x, y)| {
    |                                                ^^^^^^ expected a tuple with 3 elements, found one with 2 elements
    |
    = note: expected tuple `(Variable, Variable, Variable)`
               found tuple `(_, _)`

ukanren-append.rs

let mut goal = bind(("x", "y", "z"), move |(x, y, z)| {
    both(
        both(
            equal(x, "rec"),
            equal(z, "recurse")
        ),
        append(x, y, z)
    )
});

let states = goal(State::empty());