12 lines
303 B
Text
12 lines
303 B
Text
theorem Int.eq_zero_of_sign_eq_zero' : ∀ {a : Int}, sign a = 0 → a = 0
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| 0, _ => rfl
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def foo (a : Int) : Bool :=
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match a with
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| Int.ofNat 0 => true
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| Int.ofNat 1 => true
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| _ => false
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example : ∀ {a : Int}, foo a = true → a = 0 ∨ a = 1
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| 0, _ => Or.inl rfl
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| 1, _ => Or.inr rfl
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