Lemma duplication ite_self and ite_id
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Description
We currently have both ite_self and ite_id which are both, up to argument order, identical.
There is more duplication between Init.SimpLemmas and Init.ByCases.
I’d say these lemmas are useful independent of simp and by_cases, and would suggest consolidating them in, say, a module Init.Ite dedicated to lemmas about ite and dite.
Versions
7dc1ceb8d4312850b39cef9e751e0a3b651946e3
Impact
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Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
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- Open a pull request that references the issue number.
Research direction
Start by comparing the relevant lemmas in Init.SimpLemmas and Init.ByCases, including ite_self and ite_id, and identify the other duplication mentioned in the issue. Evaluate consolidating the shared ite and dite lemmas in a new Init.Ite module, then update references and imports so the existing uses continue to work without duplicate definitions.
Written by the indexing model from the issue text.
Assessment
- Domain
- compilers
- Issue type
- Refactor
- Difficulty
- 5/5
- Estimated time
- Over a week
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100