12 lines
277 B
Text
12 lines
277 B
Text
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import data.nat
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inductive Diff ( n : nat ) : nat -> Type :=
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| Base : Diff n n
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| Step : Π (m : nat), Diff n (nat.succ m) -> Diff n m
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definition checkDiff : Π (n m : nat), Diff n m -> Prop
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| n _ (Diff.Base n) := true
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| n m (Diff.Step m s) := checkDiff n _ s
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print checkDiff
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