Function zero 

pub fn zero() -> Term

Produces a Stump-Fu-encoded number zero; equivalent to boolean::fls.

ZERO ≡ λf.λa.a ≡ λ λ 1 ≡ FALSE

Example

use lambda_calculus::data::num::stumpfu::zero;
use lambda_calculus::*;

assert_eq!(zero(), 0.into_stumpfu());