30 lines
470 B
Text
30 lines
470 B
Text
namespace Ex1
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mutual
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def isEven : Nat → Bool
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| 0 => true
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| n+1 => isOdd n
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def isOdd : Nat → Bool
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| 0 => false
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| n+1 => isEven n
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end
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termination_by' measure fun
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| Sum.inl n => n
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| Sum.inr n => n
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#print isEven
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#print isOdd
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#print isEven._mutual
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end Ex1
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namespace Ex2
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mutual
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def isEven : Nat → Bool
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| 0 => true
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| n+1 => isOdd n
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def isOdd : Nat → Bool
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| 0 => false
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| n+1 => isEven n
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end
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termination_by _ n => n
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end Ex2
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