Function lambda_calculus::booleans::or

pub fn or() -> Term

Applied to two Church-encoded booleans it returns their Church-encoded disjunction.

OR := λpq.p p q = λ λ 2 2 1

Examples

use lambda_calculus::booleans::{or, tru, fls};
use lambda_calculus::reduction::beta;
use lambda_calculus::reduction::Order::*;

assert_eq!(beta(app!(or(), tru(), tru()), &Normal, 0), tru());
assert_eq!(beta(app!(or(), tru(), fls()), &Normal, 0), tru());
assert_eq!(beta(app!(or(), fls(), tru()), &Normal, 0), tru());
assert_eq!(beta(app!(or(), fls(), fls()), &Normal, 0), fls());