sig
  type t =
      [ `Alias
      | `Arrayvar
      | `Binding
      | `Builtin
      | `Command
      | `Directory
      | `Disabled
      | `Enabled
      | `Export
      | `File
      | `Function
      | `Group
      | `Helptopic
      | `Hostname
      | `Job
      | `Keyword
      | `Running
      | `Service
      | `Setopt
      | `Shopt
      | `Signal
      | `Stopped
      | `User
      | `Variable ]
end