leanprover-community / leanprover-community/lean
Universe levels are ignored when using projection notation
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- Dominant language
- C++
- Stars
- 434
- Forks
- 79
- PR merge metrics
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Description
... if the projection notation can also be interpreted as a single name:
def foo := none.get_or_else.{3 4 5} 1 -- succeeds
def bar := (none).get_or_else.{3 4 5} 1 -- fails (as expected, but error message could be better)
foo is expected to fail, either because specifying universe levels is not supported in projection notation, or because it is supported, but these are wrong universes.
Contributor guide
First steps
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Research direction
No file or test is named. Start by reproducing the two Lean definitions and tracing projection notation when universe levels are supplied; clarify whether such levels should be rejected or validated, then ensure the failing example reports the intended error.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- cpp
- Domain
- compilers
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Needs clarification
- Newbie friendliness
- 25/100