27 lines
872 B
Text
27 lines
872 B
Text
import logic data.num
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open tactic inhabited
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namespace foo
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inductive sum (A : Type) (B : Type) : Type :=
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| inl : A → sum A B
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| inr : B → sum A B
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theorem inl_inhabited {A : Type} (B : Type) (H : inhabited A) : inhabited (sum A B)
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:= inhabited.destruct H (λ a, inhabited.mk (sum.inl B a))
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theorem inr_inhabited (A : Type) {B : Type} (H : inhabited B) : inhabited (sum A B)
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:= inhabited.destruct H (λ b, inhabited.mk (sum.inr A b))
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notation `(` h `|` r:(foldl `|` (e r, tactic.or_else r e) h) `)` := r
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infixl `;`:15 := tactic.and_then
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reveal inl_inhabited inr_inhabited
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definition my_tac := fixpoint (λ t, ( apply @inl_inhabited; t
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| apply @inr_inhabited; t
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| apply @num.is_inhabited
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))
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tactic_hint my_tac
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theorem T : inhabited (sum false num)
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end foo
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