(command.If
  arms: [
    (if_arm
      cond: (condition.Shell commands:[(C {<test>} {($ Id.VSub_Number 1)})])
      action: [
        (command.Pipeline
          children: [
            (C {<'/usr/lib/refer/mkey'>} {($ Id.VSub_Star '*')})
            (C {<'/usr/lib/refer/inv'>} {<Id.Lit_Underscore _> ($ Id.VSub_Number 1)})
          ]
          negated: F
          stderr_indices: []
        )
        (C {<mv>} {<Id.Lit_Underscore _> ($ Id.VSub_Number 1) <.ia>} {($ Id.VSub_Number 1) <.ia>})
        (C {<mv>} {<Id.Lit_Underscore _> ($ Id.VSub_Number 1) <.ib>} {($ Id.VSub_Number 1) <.ib>})
        (C {<mv>} {<Id.Lit_Underscore _> ($ Id.VSub_Number 1) <.ic>} {($ Id.VSub_Number 1) <.ic>})
      ]
      spids: [43 50]
    )
  ]
  else_action: [
    (C {<echo>} 
      {
        (SQ <'Usage:  indxbib database [ ... ]\n'> <'\tfirst argument is the basename for indexes\n'> 
          <'\tindexes will be called database.{ia,ib,ic}'>
        )
      }
    )
  ]
  redirects: []
)