#[must_use = "this returns the result of the operation, \
without modifying the original"]
#[inline(always)]
+ #[rustc_allow_const_fn_unstable(const_cmp)]
pub const fn signum(self) -> Self {
- match self {
- n if n > 0 => 1,
- 0 => 0,
- _ => -1,
- }
+ // Picking the right way to phrase this is complicated
+ // (<https://graphics.stanford.edu/~seander/bithacks.html#CopyIntegerSign>)
+ // so delegate it to `Ord` which is already producing -1/0/+1
+ // exactly like we need and can be the place to deal with the complexity.
+ self.cmp(&0) as _
}
/// Returns `true` if `self` is positive and `false` if the number is zero or