Move to intra-doc links for library/core/src/panic.rs
Helps with #75080.
@rustbot modify labels: T-doc, A-intra-doc-links, T-rustdoc
Known issues:
* Link from `core` to `std` (#74481):
[`set_hook`]
[`String`]
Add more examples to lexicographic cmp on Iterators.
Given two arrays of T1 and T2, the most important rule of lexicographical comparison is that two arrays
of equal length will be compared until the first difference occured.
The examples provided only focuses on the second rule that says that the
shorter array will be filled with some T2 that is less than every T1.
Which is only possible because of the first rule.
rename get_{ref, mut} to assume_init_{ref,mut} in Maybeuninit
References #63568
Rework with comments addressed from #66174
Have replaced most of the occurrences I've found, hopefully didn't miss out anything
r? @RalfJung
(thanks @danielhenrymantilla for the initial work on this)
Get rid of bounds check in slice::chunks_exact() and related function…
…s during construction
LLVM can't figure out in
let rem = self.len() % chunk_size;
let len = self.len() - rem;
let (fst, snd) = self.split_at(len);
and
let rem = self.len() % chunk_size;
let (fst, snd) = self.split_at(rem);
that the index passed to split_at() is smaller than the slice length and
adds a bounds check plus panic for it.
Apart from removing the overhead of the bounds check this also allows
LLVM to optimize code around the ChunksExact iterator better.
Use intra-doc links for `core/src/slice.mod.rs`
partial help in #75080
r? @jyn514
- most are using primitive types links, which cannot be used with intra links at the moment
- also `std` cannot be referenced in any link, `std::ptr::NonNull` and `std::slice` could not be referenced
Make some Ordering methods const
Constify the following methods of `core::cmp::Ordering`:
- `reverse`
- `then`
Possible because of #49146 (Allow `if` and `match` in constants).
Tracking issue: #76113
LLVM can't figure out in
let rem = self.len() % chunk_size;
let len = self.len() - rem;
let (fst, snd) = self.split_at(len);
and
let rem = self.len() % chunk_size;
let (fst, snd) = self.split_at(rem);
that the index passed to split_at() is smaller than the slice length and
adds a bounds check plus panic for it.
Apart from removing the overhead of the bounds check this also allows
LLVM to optimize code around the ChunksExact iterator better.
These are unsafe variants of the non-unchecked functions and don't do
any bounds checking.
For the time being these are not public and only a preparation for the
following commit. Making it public and stabilization can follow later
and be discussed in https://github.com/rust-lang/rust/issues/76014 .
`alloc::slice` uses `core::slice` functions, documentation are copied
from there and the links as well without resolution. `crate::ptr...`
cannot be resolved in `alloc::slice`, but `ptr` itself is imported in
both `alloc::slice` and `core::slice`, so we used that instead.
Move to intra-doc links for library/core/src/sync/atomic.rs
Helps with #75080.
@rustbot modify labels: T-doc, A-intra-doc-links, T-rustdoc
Known issues:
* Link from core to std:
[`Arc`]
[`std:🧵:yield_now`]
[`std:🧵:sleep`]
[`std::sync::Mutex`]
The most important rule of lexicographical comparison is that two arrays
of equal length will be compared until the first difference occured.
The examples provided only focuses on the second rule that says that the
shorter array will be filled with some T2 that is less than every T.
Which is only possible because of the first rule.
Fix potential UB in align_offset doc examples
Currently it takes a pointer only to the first element in the array, this changes the code to take a pointer to the whole array.
miri can't catch this right now because it later calls `x.len()` which re-tags the pointer for the whole array.
https://github.com/rust-lang/miri/issues/1526#issuecomment-680897144
Unconfuse Unpin docs a bit
* Don't say that Unpin is used to prevent moves, because it is used
to *allow* moves
* Be more precise about kindedness of things, it is
`Pin<Pointer<Data>>`, rather than just `Pin<Pointer>`.
I would like to propose these two simple methods for stabilization:
- Knowing that a range is exhaused isn't otherwise trivial
- Clippy would like to suggest them, but had to do extra work to disable that path <https://github.com/rust-lang/rust-clippy/issues/3807> because they're unstable
- These work on `PartialOrd`, consistently with now-stable `contains`, and are thus more general than iterator-based approaches that need `Step`
- They've been unchanged for some time, and have picked up uses in the compiler
- Stabilizing them doesn't block any future iterator-based is_empty plans, as the inherent ones are preferred in name resolution
* Don't say that Unpin is used to prevent moves, because it is used
to *allow* moves
* Be more precise about kindedness of things, it is
`Pin<Pointer<Data>>`, rather than just `Pin<Pointer>`.
Report an ambiguity if both modules and primitives are in scope for intra-doc links
Closes https://github.com/rust-lang/rust/issues/75381
- Add a new `prim@` disambiguator, since both modules and primitives are in the same namespace
- Refactor `report_ambiguity` into a closure
Additionally, I noticed that rustdoc would previously allow `[struct@char]` if `char` resolved to a primitive (not if it had a DefId). I fixed that and added a test case.
I also need to update libstd to use `prim@char` instead of `type@char`. If possible I would also like to refactor `ambiguity_error` to use `Disambiguator` instead of its own hand-rolled match - that ran into issues with `prim@` (I updated one and not the other) and it would be better for them to be in sync.
Use allow(unused_imports) instead of cfg(doc) for imports used only for intra-doc links
This prevents links from breaking when items are re-exported in a
different crate and the original isn't being documented.
Spotted in https://github.com/rust-lang/rust/pull/75832#discussion_r475275837 (thanks ollie!)
r? @ollie27
Fix typo in documentation of i32 wrapping_abs()
Hi!
I was reading through the std library docs and noticed that this section flowed a bit oddly; comparing it against https://doc.rust-lang.org/std/primitive.i32.html#method.wrapping_div and https://doc.rust-lang.org/std/primitive.i32.html#method.wrapping_neg , I noticed that those two pieces of documentation used a semicolon here.
This is my first time submitting a PR to this repo. Am I doing this right? Are tiny typo-fix PRs like this worth submitting, or are they not a good use of time?
Thank you!
stabilize ptr_offset_from
This stabilizes ptr::offset_from, and closes https://github.com/rust-lang/rust/issues/41079. It also removes the deprecated `wrapping_offset_from`. This function was deprecated 19 days ago and was never stable; given an FCP of 10 days and some waiting time until FCP starts, that leaves at least a month between deprecation and removal which I think is fine for a nightly-only API.
Regarding the open questions in https://github.com/rust-lang/rust/issues/41079:
* Should offset_from abort instead of panic on ZSTs? -- As far as I know, there is no precedent for such aborts. We could, however, declare this UB. Given that the size is always known statically and the check thus rather cheap, UB seems excessive.
* Should there be more methods like this with different restrictions (to allow nuw/nsw, perhaps) or that return usize (like how isize-taking offset is more conveniently done with usize-taking add these days)? -- No reason to block stabilization on that, we can always add such methods later.
Also nominating the lang team because this exposes an intrinsic.
The stabilized method is best described [by its doc-comment](56d4b2d69a/src/libcore/ptr/const_ptr.rs (L227)). The documentation forgot to mention the requirement that both pointers must "have the same provenance", aka "be derived from pointers to the same allocation", which I am adding in this PR. This is a precondition that [Miri already implements](https://play.rust-lang.org/?version=nightly&mode=debug&edition=2018&gist=a3b9d0a07a01321f5202cd99e9613480) and that, should LLVM ever obtain a `psub` operation to subtract pointers, will likely be required for that operation (following the semantics in [this paper](https://people.mpi-sws.org/~jung/twinsem/twinsem.pdf)).
Move to intra-doc links for library/core/src/alloc/{layout, global, mod}.rs
Helps with #75080. The files already contained intra-doc links, so there are only minor changes.
@rustbot modify labels: T-doc, A-intra-doc-links, T-rustdoc
Known issues:
* [`handle_alloc_error`]: Link from `core` to `alloc` could not be resolved.
* [`slice`]: slice is a primitive type, but could not be resolved; had to use [`crate::slice`] instead.
Move to intra-doc links for /library/core/src/intrinsics.rs
Helps with #75080.
@rustbot modify labels: T-doc, A-intra-doc-links, T-rustdoc
Known issues:
* The following f32 and f64 primitive methods cannot be resolved:
f32/f64::powi
f32/f64::sqrt
f32/f64::sin
f32/f64::cos
f32/f64::powf
f32/f64::exp
f32/f64::exp2
f32/f64::ln
f32/f64::log2
f32/f64::log10
f32/f64::mul_add
f32/f64::abs
f32/f64::copysign
f32/f64::floor
f32/f64::ceil
f32/f64::trunc
f32/f64::round
* Links from core to std:
[`std::pointer::*`]
[`std::process::abort`]
[`from_raw_parts`]
[`Vec::append`]
* Links with anchors?
I provided a separate commit that replaced links with anchors by intra-doc links.
Here the anchor location information gets lost, so its questionable whether to
actually replace those links.
