Rule SerialProcessing
  output '*.b'.all
  output '*.a'.all
Flow
  rule (<T>) ==> __SerialProcessing_B_0__
  rule __SerialProcessing_A_1__ ==> (<T>)
End

Rule __SerialProcessing_B_0__
  output '*.b'.all
Flow
  rule B
End

Rule __SerialProcessing_A_1__
  output '*.a'.all
Flow
  rule A
End