e82cd9b62c
This PR refines how the `apply` tactic (and related tactics like `rewrite`) name and tag the remaining subgoals. Assigned metavariables are now filtered out *before* computing subgoal tags. As a consequence, when only one unassigned subgoal remains, it inherits the tag of the input goal instead of being given a fresh suffixed tag. User-visible effect: proof states that previously displayed tags like `case h`, `case a`, or `case upper.h` for a single remaining goal now display the input goal's tag directly (e.g. no tag at all, or `case upper`). This removes noise from `funext`, `rfl`-style, and `induction`-alternative goals when the applied lemma introduces only one non-assigned metavariable. Multi-goal applications are unaffected — their subgoals continue to receive distinguishing suffixes. This may affect users whose proofs rely on the previous tag names (for example, `case h => ...` after `funext`). Such scripts need to be updated to use the input goal's tag instead. --------- Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
8 lines
201 B
Text
8 lines
201 B
Text
α : Type ?u
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inst✝ : DecidableEq α
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i : α
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β : α → Type ?u
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f : (j : α) → β j
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x : α
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⊢ (if h : x = i then ⋯ ▸ f i else f x) = f x
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1856.lean:10:4-10:13: warning: declaration uses `sorry`
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