Dtype
  [(["a"],"list",
    [("Cons",[Tvar "a"; Tapp [Tvar "a"] "list"]); ("Nil",[])])]

Dletrec
  [("MEM","v3",
    Fun "v4"
      (Mat (Var "v4")
         [(Pcon "Nil" [],Val (Lit (Bool F)));
          (Pcon "Cons" [Pvar "v2"; Pvar "v1"],
           Log Or (App Equality (Var "v3") (Var "v2"))
             (App Opapp (App Opapp (Var "MEM") (Var "v3"))
                (Var "v1")))]))]

Dtype
  [(["a"],"regexp",
    [("Repeat",[Tapp [Tvar "a"] "regexp"]);
     ("Then",[Tapp [Tvar "a"] "regexp"; Tapp [Tvar "a"] "regexp"]);
     ("Or",[Tapp [Tvar "a"] "regexp"; Tapp [Tvar "a"] "regexp"]);
     ("Charset",[Tapp [Tvar "a"] "list"]); ("Epsilon",[])])]

Dtype [(["a"],"option",[("Some",[Tvar "a"]); ("None",[])])]

Dletrec
  [("match","v13",
    Fun "v14"
      (Fun "v15"
         (Mat (Var "v13")
            [(Pcon "Nil" [],
              Mat (Var "v14")
                [(Pcon "Nil" [],Val (Lit (Bool T)));
                 (Pcon "Cons" [Pvar "v2"; Pvar "v1"],
                  Val (Lit (Bool F)))]);
             (Pcon "Cons" [Pvar "v12"; Pvar "v11"],
              Mat (Var "v12")
                [(Pcon "Epsilon" [],
                  App Opapp
                    (App Opapp (App Opapp (Var "match") (Var "v11"))
                       (Var "v14")) (Var "v15"));
                 (Pcon "Charset" [Pvar "v5"],
                  Mat (Var "v14")
                    [(Pcon "Nil" [],Val (Lit (Bool F)));
                     (Pcon "Cons" [Pvar "v4"; Pvar "v3"],
                      Log And
                        (App Opapp (App Opapp (Var "MEM") (Var "v4"))
                           (Var "v5"))
                        (App Opapp
                           (App Opapp
                              (App Opapp (Var "match") (Var "v11"))
                              (Var "v3")) (Con "None" [])))]);
                 (Pcon "Or" [Pvar "v7"; Pvar "v6"],
                  Log Or
                    (App Opapp
                       (App Opapp
                          (App Opapp (Var "match")
                             (Con "Cons" [Var "v7"; Var "v11"]))
                          (Var "v14")) (Var "v15"))
                    (App Opapp
                       (App Opapp
                          (App Opapp (Var "match")
                             (Con "Cons" [Var "v6"; Var "v11"]))
                          (Var "v14")) (Var "v15")));
                 (Pcon "Then" [Pvar "v9"; Pvar "v8"],
                  App Opapp
                    (App Opapp
                       (App Opapp (Var "match")
                          (Con "Cons"
                             [Var "v9";
                              Con "Cons" [Var "v8"; Var "v11"]]))
                       (Var "v14")) (Var "v15"));
                 (Pcon "Repeat" [Pvar "v10"],
                  If
                    (App Equality (Var "v15")
                       (Con "Some"
                          [Con "Cons"
                             [Con "Repeat" [Var "v10"]; Var "v11"]]))
                    (Val (Lit (Bool F)))
                    (Log Or
                       (App Opapp
                          (App Opapp
                             (App Opapp (Var "match") (Var "v11"))
                             (Var "v14")) (Var "v15"))
                       (App Opapp
                          (App Opapp
                             (App Opapp (Var "match")
                                (Con "Cons"
                                   [Var "v10";
                                    Con "Cons"
                                      [Con "Repeat" [Var "v10"];
                                       Var "v11"]])) (Var "v14"))
                          (Con "Some"
                             [Con "Cons"
                                [Con "Repeat" [Var "v10"];
                                 Var "v11"]]))))])])))]