Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Add From trait for NonZero ints to NonZero ints #66479

Closed
wants to merge 2 commits into from
Closed

Add From trait for NonZero ints to NonZero ints #66479

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
0f86431
Add From trait for NonZero ints to NonZero ints
c3st7n Nov 16, 2019
5cc730c
Fix tidy errors
Nov 16, 2019
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
77 changes: 77 additions & 0 deletions src/libcore/num/mod.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -134,6 +134,83 @@ macro_rules! from_str_radix_nzint_impl {
from_str_radix_nzint_impl! { NonZeroU8 NonZeroU16 NonZeroU32 NonZeroU64 NonZeroU128 NonZeroUsize
NonZeroI8 NonZeroI16 NonZeroI32 NonZeroI64 NonZeroI128 NonZeroIsize }

// Conversion traits for NonZero integer types to wider NonZero types
macro_rules! impl_nz_from_nz {
($Small: ty, $Large: ty, $LargePrimitive: ty, #[$attr:meta], $doc: expr) => {
#[$attr]
#[doc = $doc]
impl From<$Small> for $Large {
#[inline]
fn from(small: $Small) -> $Large {
// SAFETY: we already know a NonZero will not contain a zero
unsafe {
<$Large>::new_unchecked(small.get() as $LargePrimitive)
}
}
}
};
($Small: ty, $Large: ty, $LargePrimitive: ty, #[$attr:meta]) => {
impl_nz_from_nz!($Small,
$Large,
$LargePrimitive,
#[$attr],
concat!("Converts `",
stringify!($Small),
"` to `",
stringify!($Large),
"` losslessly.

```rust
let small = core::num::", stringify!($Small), "::new(5).unwrap();
let big: core::num::", stringify!($Large), " = small.into();
"));
}
}

// NonZeroUnsigned -> NonZeroUnsigned wider
impl_nz_from_nz! { NonZeroU8, NonZeroU16, u16,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroU8, NonZeroU32, u32,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroU8, NonZeroU64, u64,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroU8, NonZeroU128, u128,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroU16, NonZeroU32, u32,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroU16, NonZeroU64, u64,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroU16, NonZeroU128, u128,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroU32, NonZeroU64, u64,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroU32, NonZeroU128, u128,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroU64, NonZeroU128, u128,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }

// NonZeroSigned -> NonZeroSigned wider
impl_nz_from_nz! { NonZeroI8, NonZeroI16, i16,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroI8, NonZeroI32, i32,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroI8, NonZeroI64, i64,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroI8, NonZeroI128, i128,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroI16, NonZeroI32, i32,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroI16, NonZeroI64, i64,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroI16, NonZeroI128, i128,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroI32, NonZeroI64, i64,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroI32, NonZeroI128, i128,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }
impl_nz_from_nz! { NonZeroI64, NonZeroI128, i128,
#[unstable(feature = "nonzero_int_to_wider_nonzero_int_lossless_conv", issue = "66196")] }

/// Provides intentionally-wrapped arithmetic on `T`.
///
/// Operations like `+` on `u32` values is intended to never overflow,
Expand Down