1629 lines
62 KiB
Rust
1629 lines
62 KiB
Rust
//! Definitions of integer that is known not to equal zero.
|
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use crate::cmp::Ordering;
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use crate::fmt;
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use crate::hash::{Hash, Hasher};
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use crate::intrinsics;
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||
use crate::marker::StructuralPartialEq;
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||
use crate::ops::{BitOr, BitOrAssign, Div, Neg, Rem};
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||
use crate::str::FromStr;
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use super::from_str_radix;
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use super::{IntErrorKind, ParseIntError};
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mod private {
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#[unstable(
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feature = "nonzero_internals",
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reason = "implementation detail which may disappear or be replaced at any time",
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issue = "none"
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)]
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#[const_trait]
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pub trait Sealed {}
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}
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/// A marker trait for primitive types which can be zero.
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///
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/// This is an implementation detail for <code>[NonZero]\<T></code> which may disappear or be replaced at any time.
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///
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/// # Safety
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///
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/// Types implementing this trait must be primitves that are valid when zeroed.
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#[unstable(
|
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feature = "nonzero_internals",
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reason = "implementation detail which may disappear or be replaced at any time",
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issue = "none"
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)]
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#[const_trait]
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pub unsafe trait ZeroablePrimitive: Sized + Copy + private::Sealed {}
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macro_rules! impl_zeroable_primitive {
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($primitive:ty) => {
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#[unstable(
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feature = "nonzero_internals",
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reason = "implementation detail which may disappear or be replaced at any time",
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issue = "none"
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||
)]
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impl const private::Sealed for $primitive {}
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#[unstable(
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feature = "nonzero_internals",
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reason = "implementation detail which may disappear or be replaced at any time",
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issue = "none"
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||
)]
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unsafe impl const ZeroablePrimitive for $primitive {}
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};
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}
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impl_zeroable_primitive!(u8);
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impl_zeroable_primitive!(u16);
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impl_zeroable_primitive!(u32);
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impl_zeroable_primitive!(u64);
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impl_zeroable_primitive!(u128);
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impl_zeroable_primitive!(usize);
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impl_zeroable_primitive!(i8);
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impl_zeroable_primitive!(i16);
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impl_zeroable_primitive!(i32);
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impl_zeroable_primitive!(i64);
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impl_zeroable_primitive!(i128);
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impl_zeroable_primitive!(isize);
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/// A value that is known not to equal zero.
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///
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/// This enables some memory layout optimization.
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/// For example, `Option<NonZero<u32>>` is the same size as `u32`:
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///
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/// ```
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/// #![feature(generic_nonzero)]
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/// use core::mem::size_of;
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///
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/// assert_eq!(size_of::<Option<core::num::NonZero<u32>>>(), size_of::<u32>());
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/// ```
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#[unstable(feature = "generic_nonzero", issue = "120257")]
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#[repr(transparent)]
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#[rustc_layout_scalar_valid_range_start(1)]
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#[rustc_nonnull_optimization_guaranteed]
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#[rustc_diagnostic_item = "NonZero"]
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pub struct NonZero<T: ZeroablePrimitive>(T);
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macro_rules! impl_nonzero_fmt {
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($Trait:ident) => {
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#[stable(feature = "nonzero", since = "1.28.0")]
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impl<T> fmt::$Trait for NonZero<T>
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where
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T: ZeroablePrimitive + fmt::$Trait,
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{
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#[inline]
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fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
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self.get().fmt(f)
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}
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}
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};
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}
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impl_nonzero_fmt!(Debug);
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impl_nonzero_fmt!(Display);
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impl_nonzero_fmt!(Binary);
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impl_nonzero_fmt!(Octal);
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impl_nonzero_fmt!(LowerHex);
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impl_nonzero_fmt!(UpperHex);
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#[stable(feature = "nonzero", since = "1.28.0")]
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impl<T> Clone for NonZero<T>
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where
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T: ZeroablePrimitive,
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{
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#[inline]
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fn clone(&self) -> Self {
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// SAFETY: The contained value is non-zero.
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unsafe { Self(self.0) }
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}
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}
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#[stable(feature = "nonzero", since = "1.28.0")]
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impl<T> Copy for NonZero<T> where T: ZeroablePrimitive {}
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#[stable(feature = "nonzero", since = "1.28.0")]
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impl<T> PartialEq for NonZero<T>
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where
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T: ZeroablePrimitive + PartialEq,
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{
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#[inline]
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fn eq(&self, other: &Self) -> bool {
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self.get() == other.get()
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}
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#[inline]
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fn ne(&self, other: &Self) -> bool {
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self.get() != other.get()
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}
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}
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#[unstable(feature = "structural_match", issue = "31434")]
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impl<T> StructuralPartialEq for NonZero<T> where T: ZeroablePrimitive + StructuralPartialEq {}
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#[stable(feature = "nonzero", since = "1.28.0")]
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impl<T> Eq for NonZero<T> where T: ZeroablePrimitive + Eq {}
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#[stable(feature = "nonzero", since = "1.28.0")]
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impl<T> PartialOrd for NonZero<T>
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where
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T: ZeroablePrimitive + PartialOrd,
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{
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#[inline]
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fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
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self.get().partial_cmp(&other.get())
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}
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#[inline]
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fn lt(&self, other: &Self) -> bool {
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self.get() < other.get()
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}
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#[inline]
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fn le(&self, other: &Self) -> bool {
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self.get() <= other.get()
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}
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#[inline]
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fn gt(&self, other: &Self) -> bool {
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self.get() > other.get()
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}
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#[inline]
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fn ge(&self, other: &Self) -> bool {
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self.get() >= other.get()
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}
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}
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#[stable(feature = "nonzero", since = "1.28.0")]
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impl<T> Ord for NonZero<T>
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where
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T: ZeroablePrimitive + Ord,
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{
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#[inline]
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fn cmp(&self, other: &Self) -> Ordering {
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self.get().cmp(&other.get())
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}
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#[inline]
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fn max(self, other: Self) -> Self {
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// SAFETY: The maximum of two non-zero values is still non-zero.
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unsafe { Self(self.get().max(other.get())) }
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}
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#[inline]
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fn min(self, other: Self) -> Self {
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// SAFETY: The minimum of two non-zero values is still non-zero.
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unsafe { Self(self.get().min(other.get())) }
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}
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#[inline]
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fn clamp(self, min: Self, max: Self) -> Self {
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// SAFETY: A non-zero value clamped between two non-zero values is still non-zero.
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unsafe { Self(self.get().clamp(min.get(), max.get())) }
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}
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}
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#[stable(feature = "nonzero", since = "1.28.0")]
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impl<T> Hash for NonZero<T>
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where
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T: ZeroablePrimitive + Hash,
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{
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#[inline]
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fn hash<H>(&self, state: &mut H)
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where
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H: Hasher,
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{
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self.get().hash(state)
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}
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}
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#[stable(feature = "from_nonzero", since = "1.31.0")]
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impl<T> From<NonZero<T>> for T
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where
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T: ZeroablePrimitive,
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{
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#[inline]
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fn from(nonzero: NonZero<T>) -> Self {
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// Call `get` method to keep range information.
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nonzero.get()
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}
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}
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#[stable(feature = "nonzero_bitor", since = "1.45.0")]
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impl<T> BitOr for NonZero<T>
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where
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T: ZeroablePrimitive + BitOr<Output = T>,
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{
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type Output = Self;
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#[inline]
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fn bitor(self, rhs: Self) -> Self::Output {
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// SAFETY: Bitwise OR of two non-zero values is still non-zero.
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unsafe { Self(self.get() | rhs.get()) }
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}
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}
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#[stable(feature = "nonzero_bitor", since = "1.45.0")]
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impl<T> BitOr<T> for NonZero<T>
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where
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T: ZeroablePrimitive + BitOr<Output = T>,
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{
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type Output = Self;
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#[inline]
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fn bitor(self, rhs: T) -> Self::Output {
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// SAFETY: Bitwise OR of a non-zero value with anything is still non-zero.
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unsafe { Self(self.get() | rhs) }
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}
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}
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#[stable(feature = "nonzero_bitor", since = "1.45.0")]
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impl<T> BitOr<NonZero<T>> for T
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where
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T: ZeroablePrimitive + BitOr<Output = T>,
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{
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type Output = NonZero<T>;
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#[inline]
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fn bitor(self, rhs: NonZero<T>) -> Self::Output {
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// SAFETY: Bitwise OR of anything with a non-zero value is still non-zero.
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unsafe { NonZero(self | rhs.get()) }
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}
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}
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#[stable(feature = "nonzero_bitor", since = "1.45.0")]
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impl<T> BitOrAssign for NonZero<T>
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where
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T: ZeroablePrimitive,
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Self: BitOr<Output = Self>,
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{
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#[inline]
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fn bitor_assign(&mut self, rhs: Self) {
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*self = *self | rhs;
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}
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}
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#[stable(feature = "nonzero_bitor", since = "1.45.0")]
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impl<T> BitOrAssign<T> for NonZero<T>
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where
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T: ZeroablePrimitive,
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Self: BitOr<T, Output = Self>,
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{
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#[inline]
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fn bitor_assign(&mut self, rhs: T) {
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*self = *self | rhs;
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}
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}
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impl<T> NonZero<T>
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where
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T: ZeroablePrimitive,
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{
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/// Creates a non-zero if the given value is not zero.
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#[stable(feature = "nonzero", since = "1.28.0")]
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#[rustc_const_stable(feature = "const_nonzero_int_methods", since = "1.47.0")]
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#[must_use]
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#[inline]
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pub const fn new(n: T) -> Option<Self> {
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// SAFETY: Memory layout optimization guarantees that `Option<NonZero<T>>` has
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// the same layout and size as `T`, with `0` representing `None`.
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unsafe { intrinsics::transmute_unchecked(n) }
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}
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|
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/// Creates a non-zero without checking whether the value is non-zero.
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/// This results in undefined behaviour if the value is zero.
|
||
///
|
||
/// # Safety
|
||
///
|
||
/// The value must not be zero.
|
||
#[stable(feature = "nonzero", since = "1.28.0")]
|
||
#[rustc_const_stable(feature = "nonzero", since = "1.28.0")]
|
||
#[must_use]
|
||
#[inline]
|
||
pub const unsafe fn new_unchecked(n: T) -> Self {
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||
match Self::new(n) {
|
||
Some(n) => n,
|
||
None => {
|
||
// SAFETY: The caller guarantees that `n` is non-zero, so this is unreachable.
|
||
unsafe {
|
||
intrinsics::assert_unsafe_precondition!(
|
||
"NonZero::new_unchecked requires the argument to be non-zero",
|
||
() => false,
|
||
);
|
||
intrinsics::unreachable()
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/// Converts a reference to a non-zero mutable reference
|
||
/// if the referenced value is not zero.
|
||
#[unstable(feature = "nonzero_from_mut", issue = "106290")]
|
||
#[must_use]
|
||
#[inline]
|
||
pub fn from_mut(n: &mut T) -> Option<&mut Self> {
|
||
// SAFETY: Memory layout optimization guarantees that `Option<NonZero<T>>` has
|
||
// the same layout and size as `T`, with `0` representing `None`.
|
||
let opt_n = unsafe { &mut *(n as *mut T as *mut Option<Self>) };
|
||
|
||
opt_n.as_mut()
|
||
}
|
||
|
||
/// Converts a mutable reference to a non-zero mutable reference
|
||
/// without checking whether the referenced value is non-zero.
|
||
/// This results in undefined behavior if the referenced value is zero.
|
||
///
|
||
/// # Safety
|
||
///
|
||
/// The referenced value must not be zero.
|
||
#[unstable(feature = "nonzero_from_mut", issue = "106290")]
|
||
#[must_use]
|
||
#[inline]
|
||
pub unsafe fn from_mut_unchecked(n: &mut T) -> &mut Self {
|
||
match Self::from_mut(n) {
|
||
Some(n) => n,
|
||
None => {
|
||
// SAFETY: The caller guarantees that `n` references a value that is non-zero, so this is unreachable.
|
||
unsafe {
|
||
intrinsics::assert_unsafe_precondition!(
|
||
"NonZero::from_mut_unchecked requires the argument to dereference as non-zero",
|
||
() => false,
|
||
);
|
||
intrinsics::unreachable()
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/// Returns the contained value as a primitive type.
|
||
#[stable(feature = "nonzero", since = "1.28.0")]
|
||
#[rustc_const_stable(feature = "const_nonzero_get", since = "1.34.0")]
|
||
#[inline]
|
||
pub const fn get(self) -> T {
|
||
// FIXME: This can be changed to simply `self.0` once LLVM supports `!range` metadata
|
||
// for function arguments: https://github.com/llvm/llvm-project/issues/76628
|
||
//
|
||
// Rustc can set range metadata only if it loads `self` from
|
||
// memory somewhere. If the value of `self` was from by-value argument
|
||
// of some not-inlined function, LLVM don't have range metadata
|
||
// to understand that the value cannot be zero.
|
||
match Self::new(self.0) {
|
||
Some(Self(n)) => n,
|
||
None => {
|
||
// SAFETY: `NonZero` is guaranteed to only contain non-zero values, so this is unreachable.
|
||
unsafe { intrinsics::unreachable() }
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
macro_rules! nonzero_integer {
|
||
(
|
||
#[$stability:meta]
|
||
Self = $Ty:ident,
|
||
Primitive = $signedness:ident $Int:ident,
|
||
$(UnsignedNonZero = $UnsignedNonZero:ident,)?
|
||
UnsignedPrimitive = $UnsignedPrimitive:ty,
|
||
|
||
// Used in doc comments.
|
||
leading_zeros_test = $leading_zeros_test:expr,
|
||
) => {
|
||
/// An integer that is known not to equal zero.
|
||
///
|
||
/// This enables some memory layout optimization.
|
||
#[doc = concat!("For example, `Option<", stringify!($Ty), ">` is the same size as `", stringify!($Int), "`:")]
|
||
///
|
||
/// ```rust
|
||
/// use std::mem::size_of;
|
||
#[doc = concat!("assert_eq!(size_of::<Option<core::num::", stringify!($Ty), ">>(), size_of::<", stringify!($Int), ">());")]
|
||
/// ```
|
||
///
|
||
/// # Layout
|
||
///
|
||
#[doc = concat!("`", stringify!($Ty), "` is guaranteed to have the same layout and bit validity as `", stringify!($Int), "`")]
|
||
/// with the exception that `0` is not a valid instance.
|
||
#[doc = concat!("`Option<", stringify!($Ty), ">` is guaranteed to be compatible with `", stringify!($Int), "`,")]
|
||
/// including in FFI.
|
||
///
|
||
/// Thanks to the [null pointer optimization],
|
||
#[doc = concat!("`", stringify!($Ty), "` and `Option<", stringify!($Ty), ">`")]
|
||
/// are guaranteed to have the same size and alignment:
|
||
///
|
||
/// ```
|
||
/// # use std::mem::{size_of, align_of};
|
||
#[doc = concat!("use std::num::", stringify!($Ty), ";")]
|
||
///
|
||
#[doc = concat!("assert_eq!(size_of::<", stringify!($Ty), ">(), size_of::<Option<", stringify!($Ty), ">>());")]
|
||
#[doc = concat!("assert_eq!(align_of::<", stringify!($Ty), ">(), align_of::<Option<", stringify!($Ty), ">>());")]
|
||
/// ```
|
||
///
|
||
/// [null pointer optimization]: crate::option#representation
|
||
#[$stability]
|
||
pub type $Ty = NonZero<$Int>;
|
||
|
||
impl $Ty {
|
||
/// The size of this non-zero integer type in bits.
|
||
///
|
||
#[doc = concat!("This value is equal to [`", stringify!($Int), "::BITS`].")]
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
///
|
||
#[doc = concat!("assert_eq!(", stringify!($Ty), "::BITS, ", stringify!($Int), "::BITS);")]
|
||
/// ```
|
||
#[stable(feature = "nonzero_bits", since = "1.67.0")]
|
||
pub const BITS: u32 = <$Int>::BITS;
|
||
|
||
/// Returns the number of leading zeros in the binary representation of `self`.
|
||
///
|
||
/// On many architectures, this function can perform better than `leading_zeros()` on the underlying integer type, as special handling of zero can be avoided.
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// Basic usage:
|
||
///
|
||
/// ```
|
||
#[doc = concat!("let n = std::num::", stringify!($Ty), "::new(", $leading_zeros_test, ").unwrap();")]
|
||
///
|
||
/// assert_eq!(n.leading_zeros(), 0);
|
||
/// ```
|
||
#[stable(feature = "nonzero_leading_trailing_zeros", since = "1.53.0")]
|
||
#[rustc_const_stable(feature = "nonzero_leading_trailing_zeros", since = "1.53.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn leading_zeros(self) -> u32 {
|
||
// SAFETY: since `self` cannot be zero, it is safe to call `ctlz_nonzero`.
|
||
unsafe { intrinsics::ctlz_nonzero(self.get() as $UnsignedPrimitive) as u32 }
|
||
}
|
||
|
||
/// Returns the number of trailing zeros in the binary representation
|
||
/// of `self`.
|
||
///
|
||
/// On many architectures, this function can perform better than `trailing_zeros()` on the underlying integer type, as special handling of zero can be avoided.
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// Basic usage:
|
||
///
|
||
/// ```
|
||
#[doc = concat!("let n = std::num::", stringify!($Ty), "::new(0b0101000).unwrap();")]
|
||
///
|
||
/// assert_eq!(n.trailing_zeros(), 3);
|
||
/// ```
|
||
#[stable(feature = "nonzero_leading_trailing_zeros", since = "1.53.0")]
|
||
#[rustc_const_stable(feature = "nonzero_leading_trailing_zeros", since = "1.53.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn trailing_zeros(self) -> u32 {
|
||
// SAFETY: since `self` cannot be zero, it is safe to call `cttz_nonzero`.
|
||
unsafe { intrinsics::cttz_nonzero(self.get() as $UnsignedPrimitive) as u32 }
|
||
}
|
||
|
||
/// Returns the number of ones in the binary representation of `self`.
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// Basic usage:
|
||
///
|
||
/// ```
|
||
/// #![feature(generic_nonzero, non_zero_count_ones)]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
/// # use std::num::*;
|
||
/// #
|
||
#[doc = concat!("let a = NonZero::<", stringify!($Int), ">::new(0b100_0000)?;")]
|
||
#[doc = concat!("let b = NonZero::<", stringify!($Int), ">::new(0b100_0011)?;")]
|
||
///
|
||
/// assert_eq!(a.count_ones(), NonZero::new(1)?);
|
||
/// assert_eq!(b.count_ones(), NonZero::new(3)?);
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
///
|
||
#[unstable(feature = "non_zero_count_ones", issue = "120287")]
|
||
#[rustc_const_unstable(feature = "non_zero_count_ones", issue = "120287")]
|
||
#[doc(alias = "popcount")]
|
||
#[doc(alias = "popcnt")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline(always)]
|
||
pub const fn count_ones(self) -> NonZero<u32> {
|
||
// SAFETY:
|
||
// `self` is non-zero, which means it has at least one bit set, which means
|
||
// that the result of `count_ones` is non-zero.
|
||
unsafe { NonZero::new_unchecked(self.get().count_ones()) }
|
||
}
|
||
|
||
nonzero_integer_signedness_dependent_methods! {
|
||
Self = $Ty,
|
||
Primitive = $signedness $Int,
|
||
$(UnsignedNonZero = $UnsignedNonZero,)?
|
||
UnsignedPrimitive = $UnsignedPrimitive,
|
||
}
|
||
|
||
/// Multiplies two non-zero integers together.
|
||
/// Checks for overflow and returns [`None`] on overflow.
|
||
/// As a consequence, the result cannot wrap to zero.
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")]
|
||
#[doc = concat!("let four = ", stringify!($Ty), "::new(4)?;")]
|
||
#[doc = concat!("let max = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MAX)?;")]
|
||
///
|
||
/// assert_eq!(Some(four), two.checked_mul(two));
|
||
/// assert_eq!(None, max.checked_mul(two));
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[stable(feature = "nonzero_checked_ops", since = "1.64.0")]
|
||
#[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn checked_mul(self, other: Self) -> Option<Self> {
|
||
if let Some(result) = self.get().checked_mul(other.get()) {
|
||
// SAFETY:
|
||
// - `checked_mul` returns `None` on overflow
|
||
// - `self` and `other` are non-zero
|
||
// - the only way to get zero from a multiplication without overflow is for one
|
||
// of the sides to be zero
|
||
//
|
||
// So the result cannot be zero.
|
||
Some(unsafe { Self::new_unchecked(result) })
|
||
} else {
|
||
None
|
||
}
|
||
}
|
||
|
||
/// Multiplies two non-zero integers together.
|
||
#[doc = concat!("Return [`", stringify!($Ty), "::MAX`] on overflow.")]
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")]
|
||
#[doc = concat!("let four = ", stringify!($Ty), "::new(4)?;")]
|
||
#[doc = concat!("let max = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MAX)?;")]
|
||
///
|
||
/// assert_eq!(four, two.saturating_mul(two));
|
||
/// assert_eq!(max, four.saturating_mul(max));
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[stable(feature = "nonzero_checked_ops", since = "1.64.0")]
|
||
#[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn saturating_mul(self, other: Self) -> Self {
|
||
// SAFETY:
|
||
// - `saturating_mul` returns `u*::MAX`/`i*::MAX`/`i*::MIN` on overflow/underflow,
|
||
// all of which are non-zero
|
||
// - `self` and `other` are non-zero
|
||
// - the only way to get zero from a multiplication without overflow is for one
|
||
// of the sides to be zero
|
||
//
|
||
// So the result cannot be zero.
|
||
unsafe { Self::new_unchecked(self.get().saturating_mul(other.get())) }
|
||
}
|
||
|
||
/// Multiplies two non-zero integers together,
|
||
/// assuming overflow cannot occur.
|
||
/// Overflow is unchecked, and it is undefined behaviour to overflow
|
||
/// *even if the result would wrap to a non-zero value*.
|
||
/// The behaviour is undefined as soon as
|
||
#[doc = sign_dependent_expr!{
|
||
$signedness ?
|
||
if signed {
|
||
concat!("`self * rhs > ", stringify!($Int), "::MAX`, ",
|
||
"or `self * rhs < ", stringify!($Int), "::MIN`.")
|
||
}
|
||
if unsigned {
|
||
concat!("`self * rhs > ", stringify!($Int), "::MAX`.")
|
||
}
|
||
}]
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
/// #![feature(nonzero_ops)]
|
||
///
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")]
|
||
#[doc = concat!("let four = ", stringify!($Ty), "::new(4)?;")]
|
||
///
|
||
/// assert_eq!(four, unsafe { two.unchecked_mul(two) });
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[unstable(feature = "nonzero_ops", issue = "84186")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const unsafe fn unchecked_mul(self, other: Self) -> Self {
|
||
// SAFETY: The caller ensures there is no overflow.
|
||
unsafe { Self::new_unchecked(self.get().unchecked_mul(other.get())) }
|
||
}
|
||
|
||
/// Raises non-zero value to an integer power.
|
||
/// Checks for overflow and returns [`None`] on overflow.
|
||
/// As a consequence, the result cannot wrap to zero.
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let three = ", stringify!($Ty), "::new(3)?;")]
|
||
#[doc = concat!("let twenty_seven = ", stringify!($Ty), "::new(27)?;")]
|
||
#[doc = concat!("let half_max = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MAX / 2)?;")]
|
||
///
|
||
/// assert_eq!(Some(twenty_seven), three.checked_pow(3));
|
||
/// assert_eq!(None, half_max.checked_pow(3));
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[stable(feature = "nonzero_checked_ops", since = "1.64.0")]
|
||
#[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn checked_pow(self, other: u32) -> Option<Self> {
|
||
if let Some(result) = self.get().checked_pow(other) {
|
||
// SAFETY:
|
||
// - `checked_pow` returns `None` on overflow/underflow
|
||
// - `self` is non-zero
|
||
// - the only way to get zero from an exponentiation without overflow is
|
||
// for base to be zero
|
||
//
|
||
// So the result cannot be zero.
|
||
Some(unsafe { Self::new_unchecked(result) })
|
||
} else {
|
||
None
|
||
}
|
||
}
|
||
|
||
/// Raise non-zero value to an integer power.
|
||
#[doc = sign_dependent_expr!{
|
||
$signedness ?
|
||
if signed {
|
||
concat!("Return [`", stringify!($Ty), "::MIN`] ",
|
||
"or [`", stringify!($Ty), "::MAX`] on overflow.")
|
||
}
|
||
if unsigned {
|
||
concat!("Return [`", stringify!($Ty), "::MAX`] on overflow.")
|
||
}
|
||
}]
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let three = ", stringify!($Ty), "::new(3)?;")]
|
||
#[doc = concat!("let twenty_seven = ", stringify!($Ty), "::new(27)?;")]
|
||
#[doc = concat!("let max = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MAX)?;")]
|
||
///
|
||
/// assert_eq!(twenty_seven, three.saturating_pow(3));
|
||
/// assert_eq!(max, max.saturating_pow(3));
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[stable(feature = "nonzero_checked_ops", since = "1.64.0")]
|
||
#[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn saturating_pow(self, other: u32) -> Self {
|
||
// SAFETY:
|
||
// - `saturating_pow` returns `u*::MAX`/`i*::MAX`/`i*::MIN` on overflow/underflow,
|
||
// all of which are non-zero
|
||
// - `self` is non-zero
|
||
// - the only way to get zero from an exponentiation without overflow is
|
||
// for base to be zero
|
||
//
|
||
// So the result cannot be zero.
|
||
unsafe { Self::new_unchecked(self.get().saturating_pow(other)) }
|
||
}
|
||
}
|
||
|
||
#[stable(feature = "nonzero_parse", since = "1.35.0")]
|
||
impl FromStr for $Ty {
|
||
type Err = ParseIntError;
|
||
fn from_str(src: &str) -> Result<Self, Self::Err> {
|
||
Self::new(from_str_radix(src, 10)?)
|
||
.ok_or(ParseIntError {
|
||
kind: IntErrorKind::Zero
|
||
})
|
||
}
|
||
}
|
||
|
||
nonzero_integer_signedness_dependent_impls!($Ty $signedness $Int);
|
||
};
|
||
|
||
(Self = $Ty:ident, Primitive = unsigned $Int:ident $(,)?) => {
|
||
nonzero_integer! {
|
||
#[stable(feature = "nonzero", since = "1.28.0")]
|
||
Self = $Ty,
|
||
Primitive = unsigned $Int,
|
||
UnsignedPrimitive = $Int,
|
||
leading_zeros_test = concat!(stringify!($Int), "::MAX"),
|
||
}
|
||
};
|
||
|
||
(Self = $Ty:ident, Primitive = signed $Int:ident, $($rest:tt)*) => {
|
||
nonzero_integer! {
|
||
#[stable(feature = "signed_nonzero", since = "1.34.0")]
|
||
Self = $Ty,
|
||
Primitive = signed $Int,
|
||
$($rest)*
|
||
leading_zeros_test = concat!("-1", stringify!($Int)),
|
||
}
|
||
};
|
||
}
|
||
|
||
macro_rules! nonzero_integer_signedness_dependent_impls {
|
||
// Impls for unsigned nonzero types only.
|
||
($Ty:ident unsigned $Int:ty) => {
|
||
#[stable(feature = "nonzero_div", since = "1.51.0")]
|
||
impl Div<$Ty> for $Int {
|
||
type Output = $Int;
|
||
|
||
/// This operation rounds towards zero,
|
||
/// truncating any fractional part of the exact result, and cannot panic.
|
||
#[inline]
|
||
fn div(self, other: $Ty) -> $Int {
|
||
// SAFETY: div by zero is checked because `other` is a nonzero,
|
||
// and MIN/-1 is checked because `self` is an unsigned int.
|
||
unsafe { intrinsics::unchecked_div(self, other.get()) }
|
||
}
|
||
}
|
||
|
||
#[stable(feature = "nonzero_div", since = "1.51.0")]
|
||
impl Rem<$Ty> for $Int {
|
||
type Output = $Int;
|
||
|
||
/// This operation satisfies `n % d == n - (n / d) * d`, and cannot panic.
|
||
#[inline]
|
||
fn rem(self, other: $Ty) -> $Int {
|
||
// SAFETY: rem by zero is checked because `other` is a nonzero,
|
||
// and MIN/-1 is checked because `self` is an unsigned int.
|
||
unsafe { intrinsics::unchecked_rem(self, other.get()) }
|
||
}
|
||
}
|
||
};
|
||
|
||
// Impls for signed nonzero types only.
|
||
($Ty:ident signed $Int:ty) => {
|
||
#[stable(feature = "signed_nonzero_neg", since = "1.71.0")]
|
||
impl Neg for $Ty {
|
||
type Output = Self;
|
||
|
||
#[inline]
|
||
fn neg(self) -> Self {
|
||
// SAFETY: negation of nonzero cannot yield zero values.
|
||
unsafe { Self::new_unchecked(self.get().neg()) }
|
||
}
|
||
}
|
||
|
||
forward_ref_unop! { impl Neg, neg for $Ty,
|
||
#[stable(feature = "signed_nonzero_neg", since = "1.71.0")] }
|
||
};
|
||
}
|
||
|
||
#[rustfmt::skip] // https://github.com/rust-lang/rustfmt/issues/5974
|
||
macro_rules! nonzero_integer_signedness_dependent_methods {
|
||
// Associated items for unsigned nonzero types only.
|
||
(
|
||
Self = $Ty:ident,
|
||
Primitive = unsigned $Int:ident,
|
||
UnsignedPrimitive = $Uint:ty,
|
||
) => {
|
||
/// The smallest value that can be represented by this non-zero
|
||
/// integer type, 1.
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
#[doc = concat!("assert_eq!(", stringify!($Ty), "::MIN.get(), 1", stringify!($Int), ");")]
|
||
/// ```
|
||
#[stable(feature = "nonzero_min_max", since = "1.70.0")]
|
||
pub const MIN: Self = Self::new(1).unwrap();
|
||
|
||
/// The largest value that can be represented by this non-zero
|
||
/// integer type,
|
||
#[doc = concat!("equal to [`", stringify!($Int), "::MAX`].")]
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
#[doc = concat!("assert_eq!(", stringify!($Ty), "::MAX.get(), ", stringify!($Int), "::MAX);")]
|
||
/// ```
|
||
#[stable(feature = "nonzero_min_max", since = "1.70.0")]
|
||
pub const MAX: Self = Self::new(<$Int>::MAX).unwrap();
|
||
|
||
/// Adds an unsigned integer to a non-zero value.
|
||
/// Checks for overflow and returns [`None`] on overflow.
|
||
/// As a consequence, the result cannot wrap to zero.
|
||
///
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let one = ", stringify!($Ty), "::new(1)?;")]
|
||
#[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")]
|
||
#[doc = concat!("let max = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MAX)?;")]
|
||
///
|
||
/// assert_eq!(Some(two), one.checked_add(1));
|
||
/// assert_eq!(None, max.checked_add(1));
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[stable(feature = "nonzero_checked_ops", since = "1.64.0")]
|
||
#[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn checked_add(self, other: $Int) -> Option<Self> {
|
||
if let Some(result) = self.get().checked_add(other) {
|
||
// SAFETY:
|
||
// - `checked_add` returns `None` on overflow
|
||
// - `self` is non-zero
|
||
// - the only way to get zero from an addition without overflow is for both
|
||
// sides to be zero
|
||
//
|
||
// So the result cannot be zero.
|
||
Some(unsafe { Self::new_unchecked(result) })
|
||
} else {
|
||
None
|
||
}
|
||
}
|
||
|
||
/// Adds an unsigned integer to a non-zero value.
|
||
#[doc = concat!("Return [`", stringify!($Ty), "::MAX`] on overflow.")]
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let one = ", stringify!($Ty), "::new(1)?;")]
|
||
#[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")]
|
||
#[doc = concat!("let max = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MAX)?;")]
|
||
///
|
||
/// assert_eq!(two, one.saturating_add(1));
|
||
/// assert_eq!(max, max.saturating_add(1));
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[stable(feature = "nonzero_checked_ops", since = "1.64.0")]
|
||
#[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn saturating_add(self, other: $Int) -> Self {
|
||
// SAFETY:
|
||
// - `saturating_add` returns `u*::MAX` on overflow, which is non-zero
|
||
// - `self` is non-zero
|
||
// - the only way to get zero from an addition without overflow is for both
|
||
// sides to be zero
|
||
//
|
||
// So the result cannot be zero.
|
||
unsafe { Self::new_unchecked(self.get().saturating_add(other)) }
|
||
}
|
||
|
||
/// Adds an unsigned integer to a non-zero value,
|
||
/// assuming overflow cannot occur.
|
||
/// Overflow is unchecked, and it is undefined behaviour to overflow
|
||
/// *even if the result would wrap to a non-zero value*.
|
||
/// The behaviour is undefined as soon as
|
||
#[doc = concat!("`self + rhs > ", stringify!($Int), "::MAX`.")]
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
/// #![feature(nonzero_ops)]
|
||
///
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let one = ", stringify!($Ty), "::new(1)?;")]
|
||
#[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")]
|
||
///
|
||
/// assert_eq!(two, unsafe { one.unchecked_add(1) });
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[unstable(feature = "nonzero_ops", issue = "84186")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const unsafe fn unchecked_add(self, other: $Int) -> Self {
|
||
// SAFETY: The caller ensures there is no overflow.
|
||
unsafe { Self::new_unchecked(self.get().unchecked_add(other)) }
|
||
}
|
||
|
||
/// Returns the smallest power of two greater than or equal to n.
|
||
/// Checks for overflow and returns [`None`]
|
||
/// if the next power of two is greater than the type’s maximum value.
|
||
/// As a consequence, the result cannot wrap to zero.
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")]
|
||
#[doc = concat!("let three = ", stringify!($Ty), "::new(3)?;")]
|
||
#[doc = concat!("let four = ", stringify!($Ty), "::new(4)?;")]
|
||
#[doc = concat!("let max = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MAX)?;")]
|
||
///
|
||
/// assert_eq!(Some(two), two.checked_next_power_of_two() );
|
||
/// assert_eq!(Some(four), three.checked_next_power_of_two() );
|
||
/// assert_eq!(None, max.checked_next_power_of_two() );
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[stable(feature = "nonzero_checked_ops", since = "1.64.0")]
|
||
#[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn checked_next_power_of_two(self) -> Option<Self> {
|
||
if let Some(nz) = self.get().checked_next_power_of_two() {
|
||
// SAFETY: The next power of two is positive
|
||
// and overflow is checked.
|
||
Some(unsafe { Self::new_unchecked(nz) })
|
||
} else {
|
||
None
|
||
}
|
||
}
|
||
|
||
/// Returns the base 2 logarithm of the number, rounded down.
|
||
///
|
||
/// This is the same operation as
|
||
#[doc = concat!("[`", stringify!($Int), "::ilog2`],")]
|
||
/// except that it has no failure cases to worry about
|
||
/// since this value can never be zero.
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
#[doc = concat!("assert_eq!(", stringify!($Ty), "::new(7).unwrap().ilog2(), 2);")]
|
||
#[doc = concat!("assert_eq!(", stringify!($Ty), "::new(8).unwrap().ilog2(), 3);")]
|
||
#[doc = concat!("assert_eq!(", stringify!($Ty), "::new(9).unwrap().ilog2(), 3);")]
|
||
/// ```
|
||
#[stable(feature = "int_log", since = "1.67.0")]
|
||
#[rustc_const_stable(feature = "int_log", since = "1.67.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn ilog2(self) -> u32 {
|
||
Self::BITS - 1 - self.leading_zeros()
|
||
}
|
||
|
||
/// Returns the base 10 logarithm of the number, rounded down.
|
||
///
|
||
/// This is the same operation as
|
||
#[doc = concat!("[`", stringify!($Int), "::ilog10`],")]
|
||
/// except that it has no failure cases to worry about
|
||
/// since this value can never be zero.
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
#[doc = concat!("assert_eq!(", stringify!($Ty), "::new(99).unwrap().ilog10(), 1);")]
|
||
#[doc = concat!("assert_eq!(", stringify!($Ty), "::new(100).unwrap().ilog10(), 2);")]
|
||
#[doc = concat!("assert_eq!(", stringify!($Ty), "::new(101).unwrap().ilog10(), 2);")]
|
||
/// ```
|
||
#[stable(feature = "int_log", since = "1.67.0")]
|
||
#[rustc_const_stable(feature = "int_log", since = "1.67.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn ilog10(self) -> u32 {
|
||
super::int_log10::$Int(self.get())
|
||
}
|
||
|
||
/// Calculates the middle point of `self` and `rhs`.
|
||
///
|
||
/// `midpoint(a, b)` is `(a + b) >> 1` as if it were performed in a
|
||
/// sufficiently-large signed integral type. This implies that the result is
|
||
/// always rounded towards negative infinity and that no overflow will ever occur.
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
/// #![feature(num_midpoint)]
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
///
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let one = ", stringify!($Ty), "::new(1)?;")]
|
||
#[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")]
|
||
#[doc = concat!("let four = ", stringify!($Ty), "::new(4)?;")]
|
||
///
|
||
/// assert_eq!(one.midpoint(four), two);
|
||
/// assert_eq!(four.midpoint(one), two);
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[unstable(feature = "num_midpoint", issue = "110840")]
|
||
#[rustc_const_unstable(feature = "const_num_midpoint", issue = "110840")]
|
||
#[rustc_allow_const_fn_unstable(const_num_midpoint)]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn midpoint(self, rhs: Self) -> Self {
|
||
// SAFETY: The only way to get `0` with midpoint is to have two opposite or
|
||
// near opposite numbers: (-5, 5), (0, 1), (0, 0) which is impossible because
|
||
// of the unsignedness of this number and also because `Self` is guaranteed to
|
||
// never being 0.
|
||
unsafe { Self::new_unchecked(self.get().midpoint(rhs.get())) }
|
||
}
|
||
|
||
/// Returns `true` if and only if `self == (1 << k)` for some `k`.
|
||
///
|
||
/// On many architectures, this function can perform better than `is_power_of_two()`
|
||
/// on the underlying integer type, as special handling of zero can be avoided.
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// Basic usage:
|
||
///
|
||
/// ```
|
||
#[doc = concat!("let eight = std::num::", stringify!($Ty), "::new(8).unwrap();")]
|
||
/// assert!(eight.is_power_of_two());
|
||
#[doc = concat!("let ten = std::num::", stringify!($Ty), "::new(10).unwrap();")]
|
||
/// assert!(!ten.is_power_of_two());
|
||
/// ```
|
||
#[must_use]
|
||
#[stable(feature = "nonzero_is_power_of_two", since = "1.59.0")]
|
||
#[rustc_const_stable(feature = "nonzero_is_power_of_two", since = "1.59.0")]
|
||
#[inline]
|
||
pub const fn is_power_of_two(self) -> bool {
|
||
// LLVM 11 normalizes `unchecked_sub(x, 1) & x == 0` to the implementation seen here.
|
||
// On the basic x86-64 target, this saves 3 instructions for the zero check.
|
||
// On x86_64 with BMI1, being nonzero lets it codegen to `BLSR`, which saves an instruction
|
||
// compared to the `POPCNT` implementation on the underlying integer type.
|
||
|
||
intrinsics::ctpop(self.get()) < 2
|
||
}
|
||
};
|
||
|
||
// Associated items for signed nonzero types only.
|
||
(
|
||
Self = $Ty:ident,
|
||
Primitive = signed $Int:ident,
|
||
UnsignedNonZero = $Uty:ident,
|
||
UnsignedPrimitive = $Uint:ty,
|
||
) => {
|
||
/// The smallest value that can be represented by this non-zero
|
||
/// integer type,
|
||
#[doc = concat!("equal to [`", stringify!($Int), "::MIN`].")]
|
||
///
|
||
/// Note: While most integer types are defined for every whole
|
||
/// number between `MIN` and `MAX`, signed non-zero integers are
|
||
/// a special case. They have a "gap" at 0.
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
#[doc = concat!("assert_eq!(", stringify!($Ty), "::MIN.get(), ", stringify!($Int), "::MIN);")]
|
||
/// ```
|
||
#[stable(feature = "nonzero_min_max", since = "1.70.0")]
|
||
pub const MIN: Self = Self::new(<$Int>::MIN).unwrap();
|
||
|
||
/// The largest value that can be represented by this non-zero
|
||
/// integer type,
|
||
#[doc = concat!("equal to [`", stringify!($Int), "::MAX`].")]
|
||
///
|
||
/// Note: While most integer types are defined for every whole
|
||
/// number between `MIN` and `MAX`, signed non-zero integers are
|
||
/// a special case. They have a "gap" at 0.
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
#[doc = concat!("assert_eq!(", stringify!($Ty), "::MAX.get(), ", stringify!($Int), "::MAX);")]
|
||
/// ```
|
||
#[stable(feature = "nonzero_min_max", since = "1.70.0")]
|
||
pub const MAX: Self = Self::new(<$Int>::MAX).unwrap();
|
||
|
||
/// Computes the absolute value of self.
|
||
#[doc = concat!("See [`", stringify!($Int), "::abs`]")]
|
||
/// for documentation on overflow behaviour.
|
||
///
|
||
/// # Example
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let pos = ", stringify!($Ty), "::new(1)?;")]
|
||
#[doc = concat!("let neg = ", stringify!($Ty), "::new(-1)?;")]
|
||
///
|
||
/// assert_eq!(pos, pos.abs());
|
||
/// assert_eq!(pos, neg.abs());
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[stable(feature = "nonzero_checked_ops", since = "1.64.0")]
|
||
#[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn abs(self) -> Self {
|
||
// SAFETY: This cannot overflow to zero.
|
||
unsafe { Self::new_unchecked(self.get().abs()) }
|
||
}
|
||
|
||
/// Checked absolute value.
|
||
/// Checks for overflow and returns [`None`] if
|
||
#[doc = concat!("`self == ", stringify!($Ty), "::MIN`.")]
|
||
/// The result cannot be zero.
|
||
///
|
||
/// # Example
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let pos = ", stringify!($Ty), "::new(1)?;")]
|
||
#[doc = concat!("let neg = ", stringify!($Ty), "::new(-1)?;")]
|
||
#[doc = concat!("let min = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MIN)?;")]
|
||
///
|
||
/// assert_eq!(Some(pos), neg.checked_abs());
|
||
/// assert_eq!(None, min.checked_abs());
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[stable(feature = "nonzero_checked_ops", since = "1.64.0")]
|
||
#[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn checked_abs(self) -> Option<Self> {
|
||
if let Some(nz) = self.get().checked_abs() {
|
||
// SAFETY: absolute value of nonzero cannot yield zero values.
|
||
Some(unsafe { Self::new_unchecked(nz) })
|
||
} else {
|
||
None
|
||
}
|
||
}
|
||
|
||
/// Computes the absolute value of self,
|
||
/// with overflow information, see
|
||
#[doc = concat!("[`", stringify!($Int), "::overflowing_abs`].")]
|
||
///
|
||
/// # Example
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let pos = ", stringify!($Ty), "::new(1)?;")]
|
||
#[doc = concat!("let neg = ", stringify!($Ty), "::new(-1)?;")]
|
||
#[doc = concat!("let min = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MIN)?;")]
|
||
///
|
||
/// assert_eq!((pos, false), pos.overflowing_abs());
|
||
/// assert_eq!((pos, false), neg.overflowing_abs());
|
||
/// assert_eq!((min, true), min.overflowing_abs());
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[stable(feature = "nonzero_checked_ops", since = "1.64.0")]
|
||
#[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn overflowing_abs(self) -> (Self, bool) {
|
||
let (nz, flag) = self.get().overflowing_abs();
|
||
(
|
||
// SAFETY: absolute value of nonzero cannot yield zero values.
|
||
unsafe { Self::new_unchecked(nz) },
|
||
flag,
|
||
)
|
||
}
|
||
|
||
/// Saturating absolute value, see
|
||
#[doc = concat!("[`", stringify!($Int), "::saturating_abs`].")]
|
||
///
|
||
/// # Example
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let pos = ", stringify!($Ty), "::new(1)?;")]
|
||
#[doc = concat!("let neg = ", stringify!($Ty), "::new(-1)?;")]
|
||
#[doc = concat!("let min = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MIN)?;")]
|
||
#[doc = concat!("let min_plus = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MIN + 1)?;")]
|
||
#[doc = concat!("let max = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MAX)?;")]
|
||
///
|
||
/// assert_eq!(pos, pos.saturating_abs());
|
||
/// assert_eq!(pos, neg.saturating_abs());
|
||
/// assert_eq!(max, min.saturating_abs());
|
||
/// assert_eq!(max, min_plus.saturating_abs());
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[stable(feature = "nonzero_checked_ops", since = "1.64.0")]
|
||
#[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn saturating_abs(self) -> Self {
|
||
// SAFETY: absolute value of nonzero cannot yield zero values.
|
||
unsafe { Self::new_unchecked(self.get().saturating_abs()) }
|
||
}
|
||
|
||
/// Wrapping absolute value, see
|
||
#[doc = concat!("[`", stringify!($Int), "::wrapping_abs`].")]
|
||
///
|
||
/// # Example
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let pos = ", stringify!($Ty), "::new(1)?;")]
|
||
#[doc = concat!("let neg = ", stringify!($Ty), "::new(-1)?;")]
|
||
#[doc = concat!("let min = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MIN)?;")]
|
||
#[doc = concat!("# let max = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MAX)?;")]
|
||
///
|
||
/// assert_eq!(pos, pos.wrapping_abs());
|
||
/// assert_eq!(pos, neg.wrapping_abs());
|
||
/// assert_eq!(min, min.wrapping_abs());
|
||
/// assert_eq!(max, (-max).wrapping_abs());
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[stable(feature = "nonzero_checked_ops", since = "1.64.0")]
|
||
#[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn wrapping_abs(self) -> Self {
|
||
// SAFETY: absolute value of nonzero cannot yield zero values.
|
||
unsafe { Self::new_unchecked(self.get().wrapping_abs()) }
|
||
}
|
||
|
||
/// Computes the absolute value of self
|
||
/// without any wrapping or panicking.
|
||
///
|
||
/// # Example
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
#[doc = concat!("# use std::num::", stringify!($Uty), ";")]
|
||
///
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let u_pos = ", stringify!($Uty), "::new(1)?;")]
|
||
#[doc = concat!("let i_pos = ", stringify!($Ty), "::new(1)?;")]
|
||
#[doc = concat!("let i_neg = ", stringify!($Ty), "::new(-1)?;")]
|
||
#[doc = concat!("let i_min = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MIN)?;")]
|
||
#[doc = concat!("let u_max = ", stringify!($Uty), "::new(",
|
||
stringify!($Uint), "::MAX / 2 + 1)?;")]
|
||
///
|
||
/// assert_eq!(u_pos, i_pos.unsigned_abs());
|
||
/// assert_eq!(u_pos, i_neg.unsigned_abs());
|
||
/// assert_eq!(u_max, i_min.unsigned_abs());
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[stable(feature = "nonzero_checked_ops", since = "1.64.0")]
|
||
#[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")]
|
||
#[must_use = "this returns the result of the operation, \
|
||
without modifying the original"]
|
||
#[inline]
|
||
pub const fn unsigned_abs(self) -> $Uty {
|
||
// SAFETY: absolute value of nonzero cannot yield zero values.
|
||
unsafe { $Uty::new_unchecked(self.get().unsigned_abs()) }
|
||
}
|
||
|
||
/// Returns `true` if `self` is positive and `false` if the
|
||
/// number is negative.
|
||
///
|
||
/// # Example
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let pos_five = ", stringify!($Ty), "::new(5)?;")]
|
||
#[doc = concat!("let neg_five = ", stringify!($Ty), "::new(-5)?;")]
|
||
///
|
||
/// assert!(pos_five.is_positive());
|
||
/// assert!(!neg_five.is_positive());
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[must_use]
|
||
#[inline]
|
||
#[stable(feature = "nonzero_negation_ops", since = "1.71.0")]
|
||
#[rustc_const_stable(feature = "nonzero_negation_ops", since = "1.71.0")]
|
||
pub const fn is_positive(self) -> bool {
|
||
self.get().is_positive()
|
||
}
|
||
|
||
/// Returns `true` if `self` is negative and `false` if the
|
||
/// number is positive.
|
||
///
|
||
/// # Example
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let pos_five = ", stringify!($Ty), "::new(5)?;")]
|
||
#[doc = concat!("let neg_five = ", stringify!($Ty), "::new(-5)?;")]
|
||
///
|
||
/// assert!(neg_five.is_negative());
|
||
/// assert!(!pos_five.is_negative());
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[must_use]
|
||
#[inline]
|
||
#[stable(feature = "nonzero_negation_ops", since = "1.71.0")]
|
||
#[rustc_const_stable(feature = "nonzero_negation_ops", since = "1.71.0")]
|
||
pub const fn is_negative(self) -> bool {
|
||
self.get().is_negative()
|
||
}
|
||
|
||
/// Checked negation. Computes `-self`,
|
||
#[doc = concat!("returning `None` if `self == ", stringify!($Ty), "::MIN`.")]
|
||
///
|
||
/// # Example
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let pos_five = ", stringify!($Ty), "::new(5)?;")]
|
||
#[doc = concat!("let neg_five = ", stringify!($Ty), "::new(-5)?;")]
|
||
#[doc = concat!("let min = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MIN)?;")]
|
||
///
|
||
/// assert_eq!(pos_five.checked_neg(), Some(neg_five));
|
||
/// assert_eq!(min.checked_neg(), None);
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[inline]
|
||
#[stable(feature = "nonzero_negation_ops", since = "1.71.0")]
|
||
#[rustc_const_stable(feature = "nonzero_negation_ops", since = "1.71.0")]
|
||
pub const fn checked_neg(self) -> Option<Self> {
|
||
if let Some(result) = self.get().checked_neg() {
|
||
// SAFETY: negation of nonzero cannot yield zero values.
|
||
return Some(unsafe { Self::new_unchecked(result) });
|
||
}
|
||
None
|
||
}
|
||
|
||
/// Negates self, overflowing if this is equal to the minimum value.
|
||
///
|
||
#[doc = concat!("See [`", stringify!($Int), "::overflowing_neg`]")]
|
||
/// for documentation on overflow behaviour.
|
||
///
|
||
/// # Example
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let pos_five = ", stringify!($Ty), "::new(5)?;")]
|
||
#[doc = concat!("let neg_five = ", stringify!($Ty), "::new(-5)?;")]
|
||
#[doc = concat!("let min = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MIN)?;")]
|
||
///
|
||
/// assert_eq!(pos_five.overflowing_neg(), (neg_five, false));
|
||
/// assert_eq!(min.overflowing_neg(), (min, true));
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[inline]
|
||
#[stable(feature = "nonzero_negation_ops", since = "1.71.0")]
|
||
#[rustc_const_stable(feature = "nonzero_negation_ops", since = "1.71.0")]
|
||
pub const fn overflowing_neg(self) -> (Self, bool) {
|
||
let (result, overflow) = self.get().overflowing_neg();
|
||
// SAFETY: negation of nonzero cannot yield zero values.
|
||
((unsafe { Self::new_unchecked(result) }), overflow)
|
||
}
|
||
|
||
/// Saturating negation. Computes `-self`,
|
||
#[doc = concat!("returning [`", stringify!($Ty), "::MAX`]")]
|
||
#[doc = concat!("if `self == ", stringify!($Ty), "::MIN`")]
|
||
/// instead of overflowing.
|
||
///
|
||
/// # Example
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let pos_five = ", stringify!($Ty), "::new(5)?;")]
|
||
#[doc = concat!("let neg_five = ", stringify!($Ty), "::new(-5)?;")]
|
||
#[doc = concat!("let min = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MIN)?;")]
|
||
#[doc = concat!("let min_plus_one = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MIN + 1)?;")]
|
||
#[doc = concat!("let max = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MAX)?;")]
|
||
///
|
||
/// assert_eq!(pos_five.saturating_neg(), neg_five);
|
||
/// assert_eq!(min.saturating_neg(), max);
|
||
/// assert_eq!(max.saturating_neg(), min_plus_one);
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[inline]
|
||
#[stable(feature = "nonzero_negation_ops", since = "1.71.0")]
|
||
#[rustc_const_stable(feature = "nonzero_negation_ops", since = "1.71.0")]
|
||
pub const fn saturating_neg(self) -> Self {
|
||
if let Some(result) = self.checked_neg() {
|
||
return result;
|
||
}
|
||
Self::MAX
|
||
}
|
||
|
||
/// Wrapping (modular) negation. Computes `-self`, wrapping around at the boundary
|
||
/// of the type.
|
||
///
|
||
#[doc = concat!("See [`", stringify!($Int), "::wrapping_neg`]")]
|
||
/// for documentation on overflow behaviour.
|
||
///
|
||
/// # Example
|
||
///
|
||
/// ```
|
||
#[doc = concat!("# use std::num::", stringify!($Ty), ";")]
|
||
/// # fn main() { test().unwrap(); }
|
||
/// # fn test() -> Option<()> {
|
||
#[doc = concat!("let pos_five = ", stringify!($Ty), "::new(5)?;")]
|
||
#[doc = concat!("let neg_five = ", stringify!($Ty), "::new(-5)?;")]
|
||
#[doc = concat!("let min = ", stringify!($Ty), "::new(",
|
||
stringify!($Int), "::MIN)?;")]
|
||
///
|
||
/// assert_eq!(pos_five.wrapping_neg(), neg_five);
|
||
/// assert_eq!(min.wrapping_neg(), min);
|
||
/// # Some(())
|
||
/// # }
|
||
/// ```
|
||
#[inline]
|
||
#[stable(feature = "nonzero_negation_ops", since = "1.71.0")]
|
||
#[rustc_const_stable(feature = "nonzero_negation_ops", since = "1.71.0")]
|
||
pub const fn wrapping_neg(self) -> Self {
|
||
let result = self.get().wrapping_neg();
|
||
// SAFETY: negation of nonzero cannot yield zero values.
|
||
unsafe { Self::new_unchecked(result) }
|
||
}
|
||
};
|
||
}
|
||
|
||
// Use this when the generated code should differ between signed and unsigned types.
|
||
macro_rules! sign_dependent_expr {
|
||
(signed ? if signed { $signed_case:expr } if unsigned { $unsigned_case:expr } ) => {
|
||
$signed_case
|
||
};
|
||
(unsigned ? if signed { $signed_case:expr } if unsigned { $unsigned_case:expr } ) => {
|
||
$unsigned_case
|
||
};
|
||
}
|
||
|
||
nonzero_integer! {
|
||
Self = NonZeroU8,
|
||
Primitive = unsigned u8,
|
||
}
|
||
|
||
nonzero_integer! {
|
||
Self = NonZeroU16,
|
||
Primitive = unsigned u16,
|
||
}
|
||
|
||
nonzero_integer! {
|
||
Self = NonZeroU32,
|
||
Primitive = unsigned u32,
|
||
}
|
||
|
||
nonzero_integer! {
|
||
Self = NonZeroU64,
|
||
Primitive = unsigned u64,
|
||
}
|
||
|
||
nonzero_integer! {
|
||
Self = NonZeroU128,
|
||
Primitive = unsigned u128,
|
||
}
|
||
|
||
nonzero_integer! {
|
||
Self = NonZeroUsize,
|
||
Primitive = unsigned usize,
|
||
}
|
||
|
||
nonzero_integer! {
|
||
Self = NonZeroI8,
|
||
Primitive = signed i8,
|
||
UnsignedNonZero = NonZeroU8,
|
||
UnsignedPrimitive = u8,
|
||
}
|
||
|
||
nonzero_integer! {
|
||
Self = NonZeroI16,
|
||
Primitive = signed i16,
|
||
UnsignedNonZero = NonZeroU16,
|
||
UnsignedPrimitive = u16,
|
||
}
|
||
|
||
nonzero_integer! {
|
||
Self = NonZeroI32,
|
||
Primitive = signed i32,
|
||
UnsignedNonZero = NonZeroU32,
|
||
UnsignedPrimitive = u32,
|
||
}
|
||
|
||
nonzero_integer! {
|
||
Self = NonZeroI64,
|
||
Primitive = signed i64,
|
||
UnsignedNonZero = NonZeroU64,
|
||
UnsignedPrimitive = u64,
|
||
}
|
||
|
||
nonzero_integer! {
|
||
Self = NonZeroI128,
|
||
Primitive = signed i128,
|
||
UnsignedNonZero = NonZeroU128,
|
||
UnsignedPrimitive = u128,
|
||
}
|
||
|
||
nonzero_integer! {
|
||
Self = NonZeroIsize,
|
||
Primitive = signed isize,
|
||
UnsignedNonZero = NonZeroUsize,
|
||
UnsignedPrimitive = usize,
|
||
}
|