在Coq中使用MSET的示例

让我展示一个自然数有限集的简单示例:

From Coq
Require Import MSets Arith.

(* We can make a set out of an ordered type *)
Module S := Make Nat_as_OT.

Definition test := S.union (S.singleton 42)
                           (S.empty).

(* membership *)
Compute S.mem 0 test.   (* evaluates to `false` *)
Compute S.mem 42 test.  (* evaluates to `true`  *)

Compute S.is_empty test.     (* evaluates to `false` *)
Compute S.is_empty S.empty.  (* evaluates to `true` *)

你可以阅读 Coq.MSets.MSetInterface 了解操作和规范 MSet