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/*
Copyright 2024 Owain Davies
SPDX-License-Identifier: Apache-2.0 OR MIT
*/
use crate::Arbi;
use core::cmp::Ordering;
impl Arbi {
/// Return an `Ordering` indicating the sign of the number: `Ordering::Less`
/// for negative, `Ordering::Equal` for zero, `Ordering::Greater` for
/// positive.
///
/// # Examples
/// ```
/// use arbi::Arbi;
/// use core::cmp::Ordering;
///
/// let neg = Arbi::from(-123456789);
/// let zer = Arbi::zero();
/// let pos = Arbi::from(123456789);
///
/// assert_eq!(neg.sign(), Ordering::Less);
/// assert_eq!(zer.sign(), Ordering::Equal);
/// assert_eq!(pos.sign(), Ordering::Greater);
/// ```
///
/// ## Complexity
/// \\( O(1) \\)
#[inline(always)]
pub fn sign(&self) -> Ordering {
if self.size() == 0 {
Ordering::Equal
} else if self.is_negative() {
Ordering::Less
} else {
Ordering::Greater
}
}
}
#[cfg(test)]
mod tests {
use crate::Arbi;
use core::cmp::Ordering;
#[test]
fn test_sign() {
let zero = Arbi::zero();
assert_eq!(zero.sign(), Ordering::Equal);
let one = Arbi::one();
assert_eq!(one.sign(), Ordering::Greater);
let neg_one = Arbi::neg_one();
assert_eq!(neg_one.sign(), Ordering::Less);
}
}