The method involves passing editor input to the external program, wherein {TAIL ~ the external program} evaluates the input, produces corresponding output, and transmits the output back to {HEAD ~ the editor} 
The method involves passing editor input to the external program , wherein { TAIL ~ the external program } evaluates the input , produces corresponding output , and transmits the output back to { HEAD ~ the editor }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD