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use crate::fmt;
use crate::ops::{BitOr, BitOrAssign};
use crate::str::FromStr;
use super::from_str_radix;
use super::{IntErrorKind, ParseIntError};
macro_rules! doc_comment {
($x:expr, $($tt:tt)*) => {
#[doc = $x]
$($tt)*
};
}
macro_rules! impl_nonzero_fmt {
( #[$stability: meta] ( $( $Trait: ident ),+ ) for $Ty: ident ) => {
$(
#[$stability]
impl fmt::$Trait for $Ty {
#[inline]
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
self.get().fmt(f)
}
}
)+
}
}
macro_rules! nonzero_integers {
( $( #[$stability: meta] $Ty: ident($Int: ty); )+ ) => {
$(
doc_comment! {
concat!("An integer that is known not to equal zero.
This enables some memory layout optimization.
For example, `Option<", stringify!($Ty), ">` is the same size as `", stringify!($Int), "`:
```rust
use std::mem::size_of;
assert_eq!(size_of::<Option<core::num::", stringify!($Ty), ">>(), size_of::<", stringify!($Int),
">());
```"),
#[$stability]
#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
#[repr(transparent)]
#[rustc_layout_scalar_valid_range_start(1)]
#[rustc_nonnull_optimization_guaranteed]
pub struct $Ty($Int);
}
impl $Ty {
#[$stability]
#[rustc_const_stable(feature = "nonzero", since = "1.34.0")]
#[inline]
pub const unsafe fn new_unchecked(n: $Int) -> Self {
unsafe { Self(n) }
}
#[$stability]
#[rustc_const_stable(feature = "const_nonzero_int_methods", since = "1.47.0")]
#[inline]
pub const fn new(n: $Int) -> Option<Self> {
if n != 0 {
Some(unsafe { Self(n) })
} else {
None
}
}
#[$stability]
#[inline]
#[rustc_const_stable(feature = "nonzero", since = "1.34.0")]
pub const fn get(self) -> $Int {
self.0
}
}
#[stable(feature = "from_nonzero", since = "1.31.0")]
impl From<$Ty> for $Int {
doc_comment! {
concat!(
"Converts a `", stringify!($Ty), "` into an `", stringify!($Int), "`"),
#[inline]
fn from(nonzero: $Ty) -> Self {
nonzero.0
}
}
}
#[stable(feature = "nonzero_bitor", since = "1.45.0")]
impl BitOr for $Ty {
type Output = Self;
#[inline]
fn bitor(self, rhs: Self) -> Self::Output {
unsafe { $Ty::new_unchecked(self.get() | rhs.get()) }
}
}
#[stable(feature = "nonzero_bitor", since = "1.45.0")]
impl BitOr<$Int> for $Ty {
type Output = Self;
#[inline]
fn bitor(self, rhs: $Int) -> Self::Output {
unsafe { $Ty::new_unchecked(self.get() | rhs) }
}
}
#[stable(feature = "nonzero_bitor", since = "1.45.0")]
impl BitOr<$Ty> for $Int {
type Output = $Ty;
#[inline]
fn bitor(self, rhs: $Ty) -> Self::Output {
unsafe { $Ty::new_unchecked(self | rhs.get()) }
}
}
#[stable(feature = "nonzero_bitor", since = "1.45.0")]
impl BitOrAssign for $Ty {
#[inline]
fn bitor_assign(&mut self, rhs: Self) {
*self = *self | rhs;
}
}
#[stable(feature = "nonzero_bitor", since = "1.45.0")]
impl BitOrAssign<$Int> for $Ty {
#[inline]
fn bitor_assign(&mut self, rhs: $Int) {
*self = *self | rhs;
}
}
impl_nonzero_fmt! {
#[$stability] (Debug, Display, Binary, Octal, LowerHex, UpperHex) for $Ty
}
)+
}
}
nonzero_integers! {
#[stable(feature = "nonzero", since = "1.28.0")] NonZeroU8(u8);
#[stable(feature = "nonzero", since = "1.28.0")] NonZeroU16(u16);
#[stable(feature = "nonzero", since = "1.28.0")] NonZeroU32(u32);
#[stable(feature = "nonzero", since = "1.28.0")] NonZeroU64(u64);
#[stable(feature = "nonzero", since = "1.28.0")] NonZeroU128(u128);
#[stable(feature = "nonzero", since = "1.28.0")] NonZeroUsize(usize);
#[stable(feature = "signed_nonzero", since = "1.34.0")] NonZeroI8(i8);
#[stable(feature = "signed_nonzero", since = "1.34.0")] NonZeroI16(i16);
#[stable(feature = "signed_nonzero", since = "1.34.0")] NonZeroI32(i32);
#[stable(feature = "signed_nonzero", since = "1.34.0")] NonZeroI64(i64);
#[stable(feature = "signed_nonzero", since = "1.34.0")] NonZeroI128(i128);
#[stable(feature = "signed_nonzero", since = "1.34.0")] NonZeroIsize(isize);
}
macro_rules! from_str_radix_nzint_impl {
($($t:ty)*) => {$(
#[stable(feature = "nonzero_parse", since = "1.35.0")]
impl FromStr for $t {
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
})
}
}
)*}
}
from_str_radix_nzint_impl! { NonZeroU8 NonZeroU16 NonZeroU32 NonZeroU64 NonZeroU128 NonZeroUsize
NonZeroI8 NonZeroI16 NonZeroI32 NonZeroI64 NonZeroI128 NonZeroIsize }