Add TryFrom<{int}> for NonZero{int}
Adds `TryFrom<{int}> for NonZero{int}`.
It uses the existing `NonZero{int}::new()` and `Option::ok_or()` functions, meaning the checks are not repeated.
I also added tests, I tried to follow the convention I saw in the test file.
I also used `#[stable(feature = "nzint_try_from_int_conv", since = "1.46.0")]`, but I have no idea if the feature/version are correctly named or even correct.
Tweak "non-primitive cast" error
- Suggest borrowing expression if it would allow cast to work.
- Suggest using `<Type>::from(<expr>)` when appropriate.
- Minor tweak to `;` typo suggestion.
Partily address #47136.
- Suggest borrowing expression if it would allow cast to work.
- Suggest using `<Type>::from(<expr>)` when appropriate.
- Minor tweak to `;` typo suggestion.
Partily address #47136.
Stabilize float::to_int_unchecked
This renames and stabilizes unsafe floating point to integer casts, which are intended to be the substitute for the currently unsound `as` behavior, once that changes to safe-but-slower saturating casts. As such, I believe this also likely unblocks #10184 (our oldest I-unsound issue!), as once this rolls out to stable it would be far easier IMO to change the behavior of `as` to be safe by default.
This does not stabilize the trait or the associated method, as they are deemed internal implementation details (and consumers should not, generally, want to expose them, as in practice all callers likely know statically/without generics what the return type is).
Closes#67058
This renames and stabilizes unsafe floating point to integer casts, which are
intended to be the substitute for the currently unsound `as` behavior, once that
changes to safe-but-slower saturating casts.
Require stable/unstable annotations for the constness of all stable fns with a const modifier
r? @RalfJung @Centril
Every `#[stable]` const fn now needs either a `#[rustc_const_unstable]` attribute or a `#[rustc_const_stable]` attribute. You can't silently stabilize the constness of a function anymore.
As discussed in https://github.com/rust-lang/rust/issues/10184
Currently, casting a floating point number to an integer with `as` is Undefined Behavior if the value is out of range. `-Z saturating-float-casts` fixes this soundness hole by making `as` “saturate” to the maximum or minimum value of the integer type (or zero for `NaN`), but has measurable negative performance impact in some benchmarks. There is some consensus in that thread for enabling saturation by default anyway, but provide an `unsafe fn` alternative for users who know through some other mean that their values are in range.
