12 lines
312 B
Text
12 lines
312 B
Text
-- HoTT
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open is_equiv equiv eq
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definition my_rec_on_ua [recursor] {A B : Type} {P : A ≃ B → Type}
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(f : A ≃ B) (H : Π(q : A = B), P (equiv_of_eq q)) : P f :=
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right_inv equiv_of_eq f ▸ H (ua f)
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theorem foo {A B : Type} (f : A ≃ B) : A = B :=
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begin
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induction f using my_rec_on_ua,
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assumption
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end
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