anchor.diff:          [MainCommand.Workspace; MainCommand.Checkout], "checkout <version> : checkout workspace to version"
           [MainCommand.Workspace; MainCommand.Branch], "branch [<branch>] : switch to branch"
           [MainCommand.Workspace; MainCommand.InstallPackage], "install : install packages"
  -        [MainCommand.View; MainCommand.AddView], "view [--down|--src] [--up|--ref] [--modified] [--app <app-wildcard>] [--static] [--test] <viewId> <viewId-wildcard>+ : add repositories to view"
  +        [MainCommand.View; MainCommand.AddView], "view [--src] [--ref] [--modified] [--app <app-wildcard>] [--static] [--test] <viewId> <viewId-wildcard>+ : add repositories to view"
           [MainCommand.View; MainCommand.OpenView], "open <viewId> : open view with your favorite ide"
           [MainCommand.View; MainCommand.BuildView], "build [--mt] [--debug] [--version <version>] [<viewId>] : build view"
           [MainCommand.View; MainCommand.RebuildView], "rebuild [--mt] [--debug] [--version <version>] [<viewId>] : rebuild view (clean & build)"
  
positive.code: 
  type private TokenOption =
      | Debug
      | Up
      | Down
      | All
      | Bin
      | Src
  
negative.code: let rec private commandAlterView (forceDefault : bool option) (forceUpReferences : bool option) (forceDownReferences : bool option) (args : string list) =
      match args with
      | TokenOption TokenOption.Default :: tail -> tail |> commandAlterView (Some true) forceUpReferences forceDownReferences
      | TokenOption TokenOption.Ref :: tail -> tail |> commandAlterView forceDefault (Some true) forceDownReferences
      | TokenOption TokenOption.Src :: tail -> tail |> commandAlterView forceDefault forceUpReferences (Some true)
      | TokenOption TokenOption.Bin :: tail -> tail |> commandAlterView forceDefault (Some false) (Some false)
      | [ViewId name] -> Command.AlterView { Name = name ; Default = forceDefault; UpReferences = forceUpReferences; DownReferences = forceDownReferences }
      | _ -> Command.Error MainCommand.AlterView
  