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#![unstable(feature = "nonzero", reason = "deprecated", issue = "49137")]
#![rustc_deprecated(reason = "use `std::ptr::NonNull` or `std::num::NonZero*` instead",
since = "1.26.0")]
#![allow(deprecated)]
use ops::CoerceUnsized;
pub unsafe trait Zeroable {
fn is_zero(&self) -> bool;
}
macro_rules! impl_zeroable_for_pointer_types {
( $( $Ptr: ty )+ ) => {
$(
unsafe impl<T: ?Sized> Zeroable for $Ptr {
#[inline]
fn is_zero(&self) -> bool {
(*self).is_null()
}
}
)+
}
}
macro_rules! impl_zeroable_for_integer_types {
( $( $Int: ty )+ ) => {
$(
unsafe impl Zeroable for $Int {
#[inline]
fn is_zero(&self) -> bool {
*self == 0
}
}
)+
}
}
impl_zeroable_for_pointer_types! {
*const T
*mut T
}
impl_zeroable_for_integer_types! {
usize u8 u16 u32 u64 u128
isize i8 i16 i32 i64 i128
}
#[lang = "non_zero"]
#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Debug, Hash)]
pub struct NonZero<T: Zeroable>(pub(crate) T);
impl<T: Zeroable> NonZero<T> {
#[inline]
pub const unsafe fn new_unchecked(inner: T) -> Self {
NonZero(inner)
}
#[inline]
pub fn new(inner: T) -> Option<Self> {
if inner.is_zero() {
None
} else {
Some(NonZero(inner))
}
}
pub fn get(self) -> T {
self.0
}
}
impl<T: Zeroable+CoerceUnsized<U>, U: Zeroable> CoerceUnsized<NonZero<U>> for NonZero<T> {}
impl<'a, T: ?Sized> From<&'a mut T> for NonZero<*mut T> {
fn from(reference: &'a mut T) -> Self {
NonZero(reference)
}
}
impl<'a, T: ?Sized> From<&'a mut T> for NonZero<*const T> {
fn from(reference: &'a mut T) -> Self {
let ptr: *mut T = reference;
NonZero(ptr)
}
}
impl<'a, T: ?Sized> From<&'a T> for NonZero<*const T> {
fn from(reference: &'a T) -> Self {
NonZero(reference)
}
}