fix: instantiate metavariables when collecting a goal's constants#13748
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This PR fixes premise selection silently dropping relevant premises when the goal was reached via `induction`. `MVarId.getRelevantConstants` and `MVarId.getConstants` walked the raw goal type returned by `getType`, which after `induction` is `?motive arg` with `?motive` an assigned-but-unsubstituted metavariable. The constant fold treats the metavariable as an opaque leaf, so every constant in the goal predicate is lost. Instantiating metavariables first recovers them. Thanks to Xavier Généreux for the report. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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This will not see constants behind non-ground delayed assigned meta variables. It may be even more robust to walk the mvar graph and collect constants from there, without instantiations. Not sure if that's relevant in practice. |
…bles Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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I'm inclined to avoid this complexity for now, but I've left a comment in the code. |
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This PR fixes premise selection silently dropping relevant premises when the goal was reached via
induction.MVarId.getRelevantConstantsandMVarId.getConstantswalked the raw goal type returned bygetType, which afterinductionis?motive argwith?motivean assigned-but-unsubstituted metavariable. The constant fold treats the metavariable as an opaque leaf, so every constant in the goal predicate is lost. Instantiating metavariables first recovers them.Thanks to Xavier Généreux for the report.
🤖 Prepared with Claude Code