15 lines
244 B
Text
15 lines
244 B
Text
exit
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import data.nat
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open nat algebra
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theorem tst (a b : nat) (H : a = 0) : a + b = b :=
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begin
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revert H,
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match a with
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| zero := λ H, by krewrite zero_add
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| (n+1) := λ H, nat.no_confusion H
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end
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end
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reveal tst
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print definition tst
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