Migrate to the bitvec crate for bit iterators #30
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
The PrimeField::ReprBits associated type is used to specify the backing array used by bitvec's BitArray struct. Once const-generics stabilise, the changes to BitArray will enable these APIs to return a type of the form BitArray<Lsb0, Self::BitStore, Self::NUM_BITS>. We could add big-endian APIs later, but with the current API, PrimeField::to_le_bits().into_repr().rev() will iterate over the bits in big-endian order. The MSRV is now 1.44.0, matching the bitvec crate.
This was an odd interface, that wrapped a little-endian byte encoding and returned a big-endian bit stream. Its only use was for obtaining an iterator over the bits of a PrimeField element, and users now have the PrimeField::to_le_bits API (from which either endianness can be obtained).
This was an awkward attempt to enable generic access to a specific encoding endianness, in order to operate generically over the bits of a field element. Now that we have PrimeField::to_le_bits, this associated type (as well as the default dependency on the byteorder crate) is no longer necessary.
This is necessary to use the output of PrimeField::to_le_bits across threads, such as in a multiexp implementation.
str4d
commented
Sep 3, 2020
The field characteristic is not a valid field element, and we only ever want to operate over its bits, which PrimeField::char_le_bits exposes.
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Outdated suggestions cannot be applied.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.
The
Endiannesstrait,PrimeField::ReprEndiannessassociated type, andBitIteratorstruct are all removed.The MSRV is now 1.44.0, matching the bitvec crate.