anchor.diff:  open System.Text.RegularExpressions
   open System.Security.Principal
   
  +/// Represents a route.
   type Route = {
           Verb : string
           Path : string
  
positive.code:       member x.Cancel() = x.CancelF()
        member x.RootUrl = sprintf "http://%s:%s/fake/" x.ServerName x.Port
  
  let emptyListener = { 
      ServerName = ""
      Port = ""
      CancelF = id }
  
  let getSetUrlAclArgs port = 
      if Environment.OSVersion.Version.Major > 5
      then "netsh",
  
negative.code:         then raise(InvalidOperationException("Could not listen to port " + port, e))
          false
  
  /// Checks whether the http listener can be bound to the given port.
  let ensureCanBindHttpPort port =
      if not <| canListen port
      then
  