The system definition may now be the same as any file.
statement -> system
statement -> instantiation
instantiation -> INSTANTIATE classname objectname
-system -> SYSTEM classname LEFT_PARA system_def RIGHT_PARA
-system_def -> instantiation system_def
-system_def -> fta_logic
+system -> SYSTEM classname LEFT_PARA fault_tree RIGHT_PARA
fta_logic -> fta_sum
fta_sum -> fta_product PLUS fta_sum
fta_sum -> fta_product