// Copyright © 2026 Mikhail Hogrefe
//
// This file is part of Malachite.
//
// Malachite is free software: you can redistribute it and/or modify it under the terms of the GNU
// Lesser General Public License (LGPL) as published by the Free Software Foundation; either version
// 3 of the License, or (at your option) any later version. See <https://www.gnu.org/licenses/>.
use crate::natural::Natural;
use malachite_base::num::arithmetic::traits::IsUnit;
impl IsUnit for Natural {
/// Determines whether a [`Natural`] is a unit: whether it is 1, the only natural number with a
/// multiplicative inverse.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Examples
/// ```
/// use malachite_base::num::arithmetic::traits::IsUnit;
/// use malachite_base::num::basic::traits::{One, Zero};
/// use malachite_nz::natural::Natural;
///
/// assert_eq!(Natural::ONE.is_unit(), true);
/// assert_eq!(Natural::ZERO.is_unit(), false);
/// assert_eq!(Natural::from(123u32).is_unit(), false);
/// ```
#[inline]
fn is_unit(&self) -> bool {
*self == 1u32
}
}