20 lines
470 B
Text
20 lines
470 B
Text
module
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example : (if (!false) = true then id else id) false = false := by
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grind
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opaque q (h : ¬ (!false) = true) : Bool → Bool
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example : (if h : (!false) = true then id else q h) false = false := by
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grind
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example [Decidable c] : (if c then id else id) false = false := by
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grind
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opaque c : Prop
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opaque r (h : ¬ c) : Bool → Bool
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open Classical
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@[grind =] theorem rax : r h x = x := sorry
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example : (if h : c then id else r h) false = false := by
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grind
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