This PR eliminates uses of `intros x y z` (with arguments) and updates the `intros` docstring to suggest that `intro x y z` should be used instead. The `intros` tactic is historical, and can be traced all the way back to Lean 2, when `intro` could only introduce a single hypothesis. Since 2020, the `intro` tactic has superceded it. The `intros` tactic (without arguments) is currently still useful.
14 lines
508 B
Text
14 lines
508 B
Text
theorem bad : ∀ (m n : Nat), (if m = n then Ordering.eq else Ordering.gt) = Ordering.lt → False := by
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intro 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.simp.rewrite 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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intro 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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