20 lines
429 B
Text
20 lines
429 B
Text
open nat
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def below (n : nat) : nat → Prop :=
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λ i, i < n
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def f {n : nat} (v : subtype (below n)) : nat :=
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v + 1
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universe variable u
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instance pred2subtype {A : Type u} : has_coe_to_sort (A → Prop) :=
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⟨Type u, (λ p : A → Prop, subtype p)⟩
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instance coesubtype {A : Type u} {p : A → Prop} : has_coe (@coe_sort _ pred2subtype p) A :=
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⟨λ s, subtype.val s⟩
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def g {n : nat} (v : below n) : nat :=
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v + 1
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#print g
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