leanprover-community / leanprover-community/mathlib4
`mk_iff` adds too many explicit arguments
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Description
Tagging a structure with mk_iff and ext results in lemmas whose arguments are all explicit, even though our convention stipulates that
- arguments to an
ifflemma should all be implicit - an
extlemma should have its arguments implicit except for the one of the form∀ x, f x = g x(or⇑f = ⇑g) - lemmas generated by
@[mk_iff]do not follow thelowerCamelCaseconvention.
See eg https://leanprover.zulipchat.com/#narrow/stream/113488-general/topic/implicit.20mk_iff
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 by locating the implementations and generated-lemma tests for mk_iff and ext, then review the linked Zulip discussion for the intended argument conventions. Done means mk_iff produces implicit arguments for iff lemmas, ext keeps only the function-equality argument explicit, and generated lemma names follow lowerCamelCase.
Written by the indexing model from the issue text.
Assessment
- Domain
- tooling
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100