14 lines
497 B
Text
14 lines
497 B
Text
theorem bad : ∀ (m n : Nat), (if m = n then Ordering.eq else Ordering.gt) = Ordering.lt → False := by
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intros m n
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cases (Nat.decEq m n) with -- an error as expected: "alternative `isFalse` has not bee provided"
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| isTrue h =>
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set_option trace.Meta.Tactic true in
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simp [h]
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theorem bad' : ∀ (m n : Nat), (if m = n then Ordering.eq else Ordering.gt) = Ordering.lt → False := by
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intros m n
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cases (Nat.decEq m n) with
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| isTrue h =>
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simp [h]
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| isFalse h =>
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simp [h]
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