Proofs' role in Coq extractions
问题 I'm trying to understand what is the role of proofs in Coq extractions. I have the following example of floor integer division by two taken from here. For my first try I used the Admitted keyword: (*********************) (* div_2_even_number *) (*********************) Definition div_2_even_number: forall n, (Nat.Even n) -> {p:nat | n=p+p}. Proof. Admitted. (*************) (* test_even *) (*************) Definition test_even: forall n, {Nat.Even n}+{Nat.Even (pred n)}. Proof. Admitted. (******