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// 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::num::arithmetic::traits::{DivisibleByPowerOf2, ModPowerOf2};
use crate::num::conversion::traits::WrappingFrom;
macro_rules! impl_divisible_by_power_of_2_unsigned {
($t:ident) => {
impl DivisibleByPowerOf2 for $t {
/// Returns whether a number is divisible by $2^k$.
///
/// $f(x, k) = (2^k|x)$.
///
/// $f(x, k) = (\exists n \in \N : \ x = n2^k)$.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Examples
/// See [here](super::divisible_by_power_of_2#divisible_by_power_of_2).
#[inline]
fn divisible_by_power_of_2(self, pow: u64) -> bool {
self.mod_power_of_2(pow) == 0
}
}
};
}
apply_to_unsigneds!(impl_divisible_by_power_of_2_unsigned);
macro_rules! impl_divisible_by_power_of_2_signed {
($u:ident, $s:ident) => {
impl DivisibleByPowerOf2 for $s {
/// Returns whether a number is divisible by $2^k$.
///
/// $f(x, k) = (2^k|x)$.
///
/// $f(x, k) = (\exists n \in \N : x = n2^k)$.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Examples
/// See [here](super::divisible_by_power_of_2#divisible_by_power_of_2).
#[inline]
fn divisible_by_power_of_2(self, pow: u64) -> bool {
$u::wrapping_from(self).divisible_by_power_of_2(pow)
}
}
};
}
apply_to_unsigned_signed_pairs!(impl_divisible_by_power_of_2_signed);