(command.CommandList
  children: [
    (C {<_Dbg_help_add_sub>} {<set>} {<basename>} 
      {
        (SQ <'**set basename** [**on**|**off**]\n'> <'\n'> <'\n'> 
          <'Set short filenames (the basename) in debug output\n'> <'\n'> <'See also:\n'> <'---------\n'> <'\n'> <'**show basename**\n'>
        )
      }
    )
    (C {<Id.Lit_ArrayLhsOpen '_Dbg_next_complete['> <set>} 
      {<basename> <Id.Lit_ArrayLhsClose ']='> (SQ <_Dbg_complete_onoff>)}
    )
    (command.ShFunction
      name: _Dbg_do_set_basename
      body: 
        (BraceGroup
          children: [
            (C {<_Dbg_set_onoff>} {(DQ ($ Id.VSub_Number '$1'))} {(SQ <basename>)})
            (command.ControlFlow
              token: <Id.ControlFlow_Return return>
              arg_word: {($ Id.VSub_QMark '$?')}
            )
          ]
        )
    )
  ]
)