2015-11-20 17:03:17 -08:00
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-- definition id {A : Type} (a : A) := a
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2015-03-25 18:22:20 -07:00
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example (a b c : nat) : id a = id b → a = b :=
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begin
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intro H,
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2015-03-27 17:26:06 -07:00
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fold [id a, id b],
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2015-03-25 18:22:20 -07:00
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assumption
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end
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example (a b c : nat) : id a = id b → a = b :=
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begin
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intro H,
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fold (id a),
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fold (id b),
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assumption
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end
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