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// Copyright © 2024 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::basic::traits::{One, Zero};
impl From<bool> for Natural {
/// Converts a [`bool`] to 0 or 1.
///
/// This function is known as the [Iverson
/// bracket](https://en.wikipedia.org/wiki/Iverson_bracket).
///
/// $$
/// f(P) = \[P\] = \\begin{cases}
/// 1 & \text{if} \\quad P, \\\\
/// 0 & \\text{otherwise}.
/// \\end{cases}
/// $$
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Examples
/// ```
/// use malachite_nz::natural::Natural;
///
/// assert_eq!(Natural::from(false), 0);
/// assert_eq!(Natural::from(true), 1);
/// ```
#[inline]
fn from(b: bool) -> Natural {
if b {
Natural::ONE
} else {
Natural::ZERO
}
}
}