changed to use start.txt as default, to be overridden by argv[1]

main.cpp

@@ -30,6 +30,8 @@ void print_version() {
 
 int main(int argc, const char * argv[]) {
     try {
+        std::string base_url {"https://www.swiftcoder.nl/cpp1/"};
+        std::string next_url {"start.txt"};
         int opt_char, opt_val;
         struct option long_options[] = {
             {"help", no_argument, nullptr, 'h'},
@@ -60,15 +62,13 @@ int main(int argc, const char * argv[]) {
         }
         for (int i = optind; i < argc; ++i) {
             try {
-                // process file argv[i]
+                next_url = argv[i];
             } catch (const std::runtime_error& ex) {
                 std::cerr << "curly: " << ex.what() << '\n';
             }
         }
 
         bool done {false};
-        std::string base_url {"https://www.swiftcoder.nl/cpp1/"};
-        std::string next_url {"gcd.txt"};
         std::string code;
         requester req;
         interpreter proc;