Header file 900 may have definitions of virtual types and values for {HEAD ~ each virtual type} coded in {TAIL ~ a computer program} 
coded in
Header file 900 may have definitions of virtual types and values for { HEAD ~ each virtual type } coded in { TAIL ~ a computer program }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL