fix: getEqnsFor? should not panic on matchers
#11463
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When a theorem's type contains a match expression, calling `getEqnsFor?` on the generated matcher would panic with "duplicate normalized declaration name". This occurred because matchers have their equations generated separately by `Lean.Meta.Match.MatchEqs`, but `shouldGenerateEqnThms` didn't check for this, leading to conflicting equation theorem names. The fix makes `shouldGenerateEqnThms` return `false` for matchers, since their equations are already handled by the dedicated matcher equation infrastructure. Closes #11461 🤖 Prepared with Claude Code 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <[email protected]>
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This PR fixes a panic in `getEqnsFor?` when called on matchers generated from match expressions in theorem types. When a theorem's type contains a match expression (e.g., `theorem bar : (match ... with ...) = 0`), the compiler generates a matcher like `bar.match_1`. Calling `getEqnsFor?` on this matcher would panic with: ``` PANIC: duplicate normalized declaration name bar.match_1.eq_1 vs. _private...bar.match_1.eq_1 ``` This also affected the `try?` tactic, which internally uses `getEqnsFor?`. We make `shouldGenerateEqnThms` return `false` for matchers, since their equations are already generated separately by `Lean.Meta.Match.MatchEqs`. This prevents the equation generation machinery from attempting to create duplicate equation theorems. Closes #11461 Closes #10390 🤖 Prepared with Claude Code Co-authored-by: Claude <[email protected]>
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This PR fixes a panic in
getEqnsFor?when called on matchers generated from match expressions in theorem types.When a theorem's type contains a match expression (e.g.,
theorem bar : (match ... with ...) = 0), the compiler generates a matcher likebar.match_1. CallinggetEqnsFor?on this matcher would panic with:This also affected the
try?tactic, which internally usesgetEqnsFor?.We make
shouldGenerateEqnThmsreturnfalsefor matchers, since their equations are already generated separately byLean.Meta.Match.MatchEqs. This prevents the equation generation machinery from attempting to create duplicate equation theorems.Closes #11461
Closes #10390
🤖 Prepared with Claude Code