为在ANTLR4中工作的正则表达式编写语法

Question

我需要一个在ANTLR4中有效的正则表达式的有效语法。我试着写下来：

语法RegExp;

       ''Create my route

       Dim sta As New PointLatLng(TextBox1.Text, TextBox2.Text)
        Dim sto As New PointLatLng(TextBox4.Text, TextBox3.Text)
        Dim route As MapRoute = GMapProviders.OpenStreetMap.GetRoute(sta, sto, False, False, 13)
        Dim rs As New GMapRoute(route.Points, "Route1")
        Dim iOvrL As New GMapOverlay
        iOvrL.Routes.Add(rs)
        GMapa.Overlays.Add(iOvrL)

''GET POINTS
        For Each point As PointLatLng In rs.Points
            Dim pointx As String = point.Lat.ToString()
            Dim pointy As String = point.Lng.ToString()
        Next

它告诉我s和v是相互左递归的