12 lines
258 B
Text
12 lines
258 B
Text
exit
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inductive foo :=
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| a | b
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open foo
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definition decidable_eq_foo [instance] : ∀ f₁ f₂ : foo, decidable (f₁ = f₂)
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| a a := by left; reflexivity
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| a b := by right; contradiction
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| b a := by right; contradiction
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| b b := by left; reflexivity
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