lean-ja / lean-ja/lean-by-example
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- Lean
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Description
Eric Wieser: Also, == is usually used for runtime concepts, not for proving; but at runtime, all types are erased and therefore all have the same representation in memory
You can see this with #eval unsafe ptrAddrUnsafe Nat; all the types refer to the dummy address 1, and so there is no data to distinguish them by
#eval unsafe ptrAddrUnsafe Nat
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start with the linked Zulip discussion and run the issue's #eval unsafe ptrAddrUnsafe Nat example to understand the reported behavior. The issue names no repository file or test; done would require identifying the relevant learning material and documenting the runtime type-erasure explanation with a clear example.
Written by the indexing model from the issue text.
Assessment
- Domain
- documentation
- Issue type
- Documentation
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Needs clarification
- Newbie friendliness
- 25/100