(command.CommandList
  children: [
    (C {<echo>} 
      {(DQ <'warning: \''> ($ Id.VSub_Number '$0') <'\' is deprecated, use \'llvm-lit\' instead.'>)}
    )
    (C {<exec>} {<llvm-lit>} {(DQ ($ Id.VSub_At '$@'))})
  ]
)