Feature spare elements #12
Open
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This is a very early draft. method names and semantic may change.
…pare_capacity()' method
* introduces a helper union to fix simplify alignment calculations no need for cmp and phantom data anymore * add simple testcase that triggered the miri issue * change end_ptr_atomic_mut(), using the rewritten start_ptr()
These methods have the same API/Semantic than the std::Vec methods. They are useful when one wants to extend a HeaderVec in place in some complex way like for example appending chars to a u8 headervec with `encode_utf8()`
Having a HeaderVec being zero length is mostly useless because it has to reallocated instanly when anything becomes pushed. This clearly should be avoided! Nevertheless supporting zero length takes out a corner-case and a potential panic and removes the burden for users explicitly ensuring zero length HeaderVecs don't happen in practice. Generally improving software reliability.
|
Note: the last commit should go into its own 'feature-std-comatibility' branch. Once #10 that got resolved and merged i will rebase the code here onto that and refactor as needed. |
Since we always point to a valid allocation we can use NonNull here. This will benefit from the niche optimization: size_of::<HeaderVec<H,T>>() == size_of::<Option<HeaderVec<H,T>>> Also adds a test to verfiy that HeaderVec are always lean and niche optimized.
Off-By-One error when rouding to the next offset. I totally missed that a bug slipped into the offset calculation because I only tested with u8 and i32 data.
These public but undocumented and unused, i added them in hindsight but probably they are not required. Otherwise they could be re-added later.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
While my
atomic appendPR #10 targets appending to a shared headervec through a immutable reference (rather special use case), this implements the std vec like way using a mutable reference to a headervec using the spare capacity as a writable buffer and then completing this by readjusting the len.note: this includes all work on #10