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