simplify `vec!` macro
Simplify `vec!` macro by replacing 2 following branches:
- `($($x:expr),*) => (...)`
- `($($x:expr,)*) => (...)`
with one:
- `($($x:expr),* $(,)?) => (...)`
This is a minor change, however, this will make the documentation cleaner
Add or_insert_with_key to Entry of HashMap/BTreeMap
Going along with `or_insert_with`, `or_insert_with_key` provides the `Entry`'s key to the lambda, avoiding the need to either clone the key or the need to reimplement this body of this method from scratch each time.
This is useful when the initial value for a map entry is derived from the key. For example, the introductory Rust book has an example Cacher struct that takes an expensive-to-compute lambda and then can, given an argument to the lambda, produce either the cached result or execute the lambda.
---
I'm fairly new to Rust, so any optimizations, corrections to types, better names, better documentation, or whatever else would be appreciated. I'd like to thank Arnavion on freenode for helping me to implement a very similar method when I found that `or_insert_with_key` was unavailable.
As a somewhat-related note, this implements https://github.com/rust-lang/rfcs/issues/1202 from 2015, so if this pull request is accepted, that should be closed.
Going along with or_insert_with, or_insert_with_key provides the
Entry's key to the lambda, avoiding the need to either clone the
key or the need to reimplement this body of this method from
scratch each time.
This is useful when the initial value for a map entry is derived
from the key. For example, the introductory Rust book has an
example Cacher struct that takes an expensive-to-compute lambda and
then can, given an argument to the lambda, produce either the
cached result or execute the lambda.
Rearrange BTreeMap::into_iter to match range_mut.
r? @Mark-Simulacrum
I wondered why you catered for the optional root differently in `into_iter` than in `range_mut`.
Replace "rc"/"arc" lang items with Rc/Arc diagnostic items.
`Rc`/`Arc` should have no special semantics, so it seems appropriate for them to not be lang items.
r? @matthewjasper
Remove the Ord bound that was plaguing drain_filter
Now that #70795 made it superfluous. Also removes superfluous lifetime specifiers (at least I think they are).
Disable try_reserve tests on Android
Calling `realloc` with large sizes seems to be broken on older Android versions that use dlmalloc as the default allocator. This is not an issue for modern Android versions that use jemalloc.
Fixes#55861
Don't import integer and float modules, use assoc consts 2
Follow up to #70777. I missed quite a lot of places. Partially because I wanted to keep the size of the last PR down, and partially because my regexes were not good enough :)
r? @dtolnay
Keep track of position when deleting from a BTreeMap
This improves the performance of drain_filter and is needed for future Cursor support for BTreeMap.
cc @ssomers
r? @Mark-Simulacrum
Don't import integer and float modules, use assoc consts
Stop importing the standard library integer and float modules to reach the `MIN`, `MAX` and other constants. They are available directly on the primitive types now.
This PR is a follow up of #69860 which made sure we use the new constants in documentation.
This type of change touches a lot of files, and previously all my assoc int consts PRs had collisions and were accepted only after a long delay. So I'd prefer to do it in smaller steps now. Just removing these imports seem like a good next step.
r? @dtolnay
clarify comment in RawVec::into_box
On first reading I almost thought "len <= cap" would be all that there is to check here. Expand the comment to clarify that that is not the case.
Fix some aliasing issues in Vec
`Vec::extend` and `Vec::truncate` invalidated references into the vector even without reallocation, because they (implicitly) created a mutable reference covering the *entire* initialized part of the vector.
Fixes https://github.com/rust-lang/rust/issues/70301
I verified the fix by adding some new tests here that I ran in Miri.
This commit changes some usage of mem::forget into mem::ManuallyDrop
in some Vec, VecDeque, BTreeMap and Box methods.
Before the commit, the generated IR for some of the methods was
longer, and even after optimization, some unwinding artifacts were
still present.
Use associated numeric consts in documentation
Now when the associated constants on int/float types are stabilized and the recommended way of accessing said constants (#68952). We can start using it in this repository, and recommend it via documentation example code.
This PR is the reincarnation of #67913 minus the actual adding + stabilization of said constants. (EDIT: Now it's only changing the documentation. So users will see the new consts, but we don't yet update the internal code)
Because of how fast bit rot happens to PRs that touch this many files, it does not try to replace 100% of the old usage of the constants in the entire repo, but a good chunk of them.
Overhaul of the `AllocRef` trait to match allocator-wg's latest consens; Take 2
GitHub won't let me reopen#69889 so I make a new PR.
In addition to #69889 this fixes the unsoundness of `RawVec::into_box` when using allocators supporting overallocating. Also it uses `MemoryBlock` in `AllocRef` to unify `_in_place` methods by passing `&mut MemoryBlock`. Additionally, `RawVec` now checks for `size_of::<T>()` again and ignore every ZST. The internal capacity of `RawVec` isn't used by ZSTs anymore, as `into_box` now requires a length to be specified.
r? @Amanieu
fixesrust-lang/wg-allocators#38fixesrust-lang/wg-allocators#41fixesrust-lang/wg-allocators#44fixesrust-lang/wg-allocators#51
Dylan DPC