(command.CommandList
  children: [
    (C {(echo)} {(SQ (Token id:Id.Lit_Chars val:'--- pgrphack insists on an argument' span_id:11))})
    (command.CommandList
      children: [
        (command.Sentence
          child: (C {(pgrphack)})
          terminator: (Token id:Id.Op_Semi val:';' span_id:15)
        )
        (C {(echo)} {($ Id.VSub_QMark '$?')})
      ]
    )
    (C {(echo)} 
      {(SQ (Token id:Id.Lit_Chars val:'--- pgrphack complains if it cannot run program' span_id:25))}
    )
    (command.CommandList
      children: [
        (command.Sentence
          child: (C {(pgrphack)} {(./nonexistent)})
          terminator: (Token id:Id.Op_Semi val:';' span_id:31)
        )
        (C {(echo)} {($ Id.VSub_QMark '$?')})
      ]
    )
    (C {(echo)} {(SQ (Token id:Id.Lit_Chars val:'--- pgrphack runs a program' span_id:41))})
    (command.CommandList
      children: [
        (command.Sentence
          child: (C {(pgrphack)} {(echo)} {(ok)})
          terminator: (Token id:Id.Op_Semi val:';' span_id:49)
        )
        (C {(echo)} {($ Id.VSub_QMark '$?')})
      ]
    )
  ]
)