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//! Even-value predicate for [`U384`].
use super::U384;
impl U384 {
/// Returns `true` if the value is even (least significant bit is 0).
///
/// Checks the LSB of limb `[0]` (the least significant limb).
///
/// # Examples
///
/// ```
/// use cnfy_uint::u384::U384;
///
/// assert!(U384::ZERO.is_even());
/// assert!(!U384::ONE.is_even());
/// assert!(U384::from_be_limbs([0, 0, 0, 0, 0, 2]).is_even());
/// ```
#[inline]
pub fn is_even(&self) -> bool {
self.0[0] & 1 == 0
}
}
#[cfg(test)]
mod ai_tests {
use super::*;
/// Zero is even.
#[test]
fn zero() {
assert!(U384::ZERO.is_even());
}
/// One is not even.
#[test]
fn one() {
assert!(!U384::ONE.is_even());
}
/// Two is even.
#[test]
fn two() {
assert!(U384::from_be_limbs([0, 0, 0, 0, 0, 2]).is_even());
}
/// MAX (all bits set) is odd.
#[test]
fn max() {
assert!(!U384::MAX.is_even());
}
/// High-limb-only value with even LSB limb is even.
#[test]
fn high_limb_even() {
assert!(U384::from_be_limbs([1, 0, 0, 0, 0, 0]).is_even());
}
}