15 lines
441 B
Text
15 lines
441 B
Text
open decidable
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attribute [reducible]
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definition decidable_bin_rel {A : Type} (R : A → A → Prop) := Πx y, decidable (R x y)
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section
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variable {A : Type}
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variable (R : A → A → Prop)
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theorem tst1 (H : Πx y, decidable (R x y)) (a b c : A) : decidable (R a b ∧ R b a) :=
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by tactic.apply_instance
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theorem tst2 (H : decidable_bin_rel R) (a b c : A) : decidable (R a b ∧ R b a ∨ R b b) :=
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by tactic.apply_instance
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end
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