Lexer: Dead code removal

src/lex.cpp

@@ -12,9 +12,11 @@ int main (int argc, char** argv)
   {
     std::cout << "argument '" << argv[i] << "'\n";
 
-    auto all = Lexer::tokens (argv[i]);
-    for (auto token : Lexer::tokens (argv[i]))
-      std::cout << "  token '" << token.first << "' " << Lexer::typeToString (token.second) << "\n";
+    Lexer l (argv[i]);
+    std::string token;
+    Lexer::Type type;
+    while (l.token (token, type))
+      std::cout << "  token '" << token << "' " << Lexer::typeToString (type) << "\n";
   }
 }