ba1c1258d7
This PR adds support to `grind` for case splitting on implications of the form `p -> q` and `(h : p) -> q h`. See the new option `(splitImp := true)`.
25 lines
630 B
Text
25 lines
630 B
Text
reset_grind_attrs%
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reset_grind_attrs%
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theorem getElem?_eq_some_iff {l : List α} : l[i]? = some a ↔ ∃ h : i < l.length, l[i] = a := by
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induction l
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· sorry
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· cases i
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· -- Better support for implication and dependent implication.
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-- We need inequality propagation (or case-splits)
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grind
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· -- Similarly
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grind
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---
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reset_grind_attrs%
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attribute [grind] List.getElem_append_left List.getElem_append_right
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attribute [grind] List.length_cons List.length_nil
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example {l : List α} {a : α} {i : Nat} (h : i = l.length) (w) :
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(l ++ [a])[i]'w = a := by
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grind -- Similar to issue above.
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---
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