11 lines
205 B
Text
11 lines
205 B
Text
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import algebra.ring
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open algebra
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definition foo {A : Type} [s : monoid A] (a : A) :=
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a * a
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example {A : Type} [s : comm_ring A] (a b : A) (H : foo a = a) : a * a = a :=
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begin
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rewrite [↓foo a, H]
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end
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