+ print "Error: Conflicting tokens: {tks.join(" ")}"
+ exit(1)
+end
+for t in gram.tokens do
+ if t.name == "Eof" then continue
+ if dfa.retrotags.has_key(t) and not dfa.retrotags[t].is_empty then continue
+ print "Error: Token {t} matches nothing"
+ exit(1)