pbag:
   filename: secretfile.txt
   rho:      1.0
   W:        3.
   modes:
      x:     2
   int:
      array: 1,2,3
   real:
      array: 1.0,-1.0
   bool:
      array: yes,0,false
   do_output: no
   dt: LONG
   x1: 1.
   x2: .9
   choose: THE_OTHER