'''	\"  pic file | troff -mm [-Tdevname] | ...
.PH "'PIC:  File(\n(.F)''Device(\*(.T)'"
.P
.DS I
.PS 5
.ps 8
     arrow "source" "code"
LA:  box "lexical" "analyzer"
     arrow "tokens" above
P:   box "parser"
     arrow "inter-" "mediate" "code" ""
Sem: box "semantic" "checker"
     arrow

     arrow <-> up from top of LA
LC:  box "lexical" "corrector"
     arrow <-> up from top of P
Syn: box "syntactic" "corrector"
     arrow up
DMP: box "diagnostic" "message" "printer"
     arrow <-> right  from right of DMP
ST:  box "symbol" "table"
     arrow from LC.ne to DMP.sw
     arrow from Sem.nw to DMP.se
     arrow <-> from Sem.top to ST.bot
.ps
.PE
.DE
