lisp dsl in fsharp

lisp.fs

type Expr = | ListOfExpr of list<Expr>
            | Func of (list<Expr> -> Expr)
            | Macro of (list<Expr> -> list<Expr>)
            | Int of int 
            | Void;;




let rec evalArgs l = 
    match l with
     | h :: tail -> (eval h) :: evalArgs tail
     | [] -> []
     | _ -> failwith "fuck"
and eval l = 
    match l with
     | ListOfExpr ((Func f) :: tail) -> f (evalArgs tail)
     | ListOfExpr ((Macro f) :: tail) -> eval (ListOfExpr (f tail))
     | ListOfExpr ((ListOfExpr f) :: tail) -> eval (ListOfExpr f)
     | Int i -> Int i
     | Void -> Void
     | _ -> failwith "fuck";;

let rec print l = 
    match l with
     | ListOfExpr ((Func f) :: tail) -> "f(" + (ListOfExpr tail |> print) + ")"
     | ListOfExpr ((Macro f) :: tail) -> "m(" + (ListOfExpr tail |> print) + ")"
     | ListOfExpr [] -> ""
     | ListOfExpr (h :: tail) -> print h + "," + (ListOfExpr tail |> print)
     | Int i -> i.ToString()
     | Void -> "Void"
     | _ -> failwith "fuck";;


let plus args= 
    let rec plusInt arguments = 
        match arguments with
         | (Int h) :: t -> h + plusInt t
         | (ListOfExpr h) :: t -> plusInt h  + plusInt t
         | [] -> 0
         | _ -> failwith "fuck" in Int (plusInt args);;

let rec doubleIntExp args: list<Expr>= 
    match args with
         | Int h :: tail -> Int h :: Int h :: (doubleIntExp tail) 
         | ListOfExpr h :: tail -> (doubleIntExp h) @ (doubleIntExp tail) 
         | h :: tail -> h :: (doubleIntExp tail) 
         | [] -> []

         | _ -> failwith "fuck";;


let script  = ListOfExpr [Macro doubleIntExp; ListOfExpr [Func plus;Int 2;Int 3; Int 4]];;


[<EntryPoint>]
let main argv = 
    script|> eval |> print |> printfn "Res %s" 
    System.Console.ReadKey() |> ignore
    0