labmda.swift

@discardableResult func cons(_ x: Any, _ y: Any) -> (((Any, Any) -> Any) -> Any) {
    return { m in m(x, y) }
}

@discardableResult func car(_ z: (((Any, Any) -> Any) -> Any)) -> Any {
    return z { p, q in p }
}

@discardableResult func cdr(_ z: (((Any, Any) -> Any) -> Any)) -> Any {
    return z { p, q in q }
}

car(cons(1, 2))
cdr(cons(1, 2))
print(car(cons(1, cons(2, 3)))) // => 1