Added warnings for unused terminals

src/inputparser.cpp

@@ -9,7 +9,6 @@
 
 namespace {
     std::set<std::string> getTerminals(std::string file) {
-        std::set<std::string> terminals;
 		std::fstream f(file);
 		return lxs::input::InputParser::getTokens(f);
     }   
@@ -41,6 +40,21 @@ namespace pds {
 			}
 		}
 
+		bool found_token;
+		for(auto& term : cnf.grammar.terminals) {
+			found_token = false;
+			for(auto& rule : cnf.grammar.rules) {
+				for(auto& tail_value : rule->tail) {
+					if (tail_value == term) {
+						found_token = true;
+						break;
+					}
+				}
+				if (found_token) break;
+			}
+			if (!found_token)
+				std::cout << "Warning: Terminal '" << term << "' is not been used." << std::endl;
+		}
 
         return cnf;
     }