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`const fn` hashing

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#288 4 comments 1 reaction 0 assignees View on GitHub

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
25/100
Issue type
Feature
Clarity
Needs clarification
Activity status
Stale
Tech stack
rust
Domain
cryptography

Research direction

Start by reviewing the Digest family of traits and Rust's const fn restrictions, which the issue identifies as the main obstacle. No implementation files, tests, or concrete acceptance criteria are named; the work would first need an agreed approach and a definition of what compile-time Shake256 hashing should support.

Written by the indexing model from the issue text.

Description

Hi!

I'm using Shake256 in a setting where all input data is known at compile-time, a case where the hash value could be computed at compile-time too.

I've been using tiny-keccak before (I'm not sure why anymore, exactly), and I started toying with it to support const fn hashing. I've bounced on some hurdles, which is why I made that issue.

This week I realized I could probably start the same discussion here: how painful would const fn-hashing be to implement? I feel like it would probably not work due to the Digest family of traits (trait fns cannot be const afaik), but I'd nevertheless would want to discuss!

Best regards,

Ruben

Dominant language
Rust
Stars
2.3k
Forks
343
Avg merge
1h 27m
Merged PRs (30d)
5

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