app.fs

let matches (pattern : string) (x : string) : bool =
    let rec matchesL pattern x =
        match pattern, x with
        | [], [] -> true
        | '?'::pTail, xHead::xTail -> matchesL pTail xTail || matchesL pTail x
        | '*'::pTail, xHead::xTail -> matchesL pTail xTail || matchesL pTail x || matchesL pattern xTail
        | pHead::pTail, xHead::xTail when pHead = xHead -> matchesL pTail xTail
        | _ -> false

    matchesL (Seq.toList pattern) (Seq.toList x)

let findMatches (pattern : string) (xs : seq<string>) : seq<string> =
    Seq.where (matches pattern) xs

[<EntryPoint>]
let main argv = 
    ["crisis"; "cristian"; "cris"; "acris"; "crielikeababis"; "criesd"]
    |> findMatches "*a?" 
    |> String.concat ","
    |> printfn "Result is %s"
    System.Console.ReadLine() |> ignore
    0