Method parse

test-app/runtime/src/main/cpp/ada/ada.h:10254–10502

template <url_pattern_regex::regex_concept regex_provider>
tl::expected<url_pattern_init, errors>
constructor_string_parser<regex_provider>::parse(std::string_view input) {
  ada_log("constructor_string_parser::parse input=", input);
  // Let parser be a new constructor string parser whose input is input and
  // token list is the result of running tokenize given input and "lenient".
  auto token_list = tokenize(input, token_policy::lenient);
  if (!token_list) {
    return tl::unexpected(token_list.error());
  }
  auto parser = constructor_string_parser(input, std::move(*token_list));

  // While parser's token index is less than parser's token list size:
  while (parser.token_index < parser.token_list.size()) {
    // Set parser's token increment to 1.
    parser.token_increment = 1;

    // If parser's token list[parser's token index]'s type is "end" then:
    if (parser.token_list[parser.token_index].type == token_type::END) {
      // If parser's state is "init":
      if (parser.state == State::INIT) {
        // Run rewind given parser.
        parser.rewind();
        // If the result of running is a hash prefix given parser is true, then
        // run change state given parser, "hash" and 1.
        if (parser.is_hash_prefix()) {
          parser.change_state(State::HASH, 1);
        } else if (parser.is_search_prefix()) {
          // Otherwise if the result of running is a search prefix given parser
          // is true: Run change state given parser, "search" and 1.
          parser.change_state(State::SEARCH, 1);
        } else {
          // Run change state given parser, "pathname" and 0.
          parser.change_state(State::PATHNAME, 0);
        }
        // Increment parser's token index by parser's token increment.
        parser.token_index += parser.token_increment;
        // Continue.
        continue;
      }

      if (parser.state == State::AUTHORITY) {
        // If parser's state is "authority":
        // Run rewind and set state given parser, and "hostname".
        parser.rewind();
        parser.change_state(State::HOSTNAME, 0);
        // Increment parser's token index by parser's token increment.
        parser.token_index += parser.token_increment;
        // Continue.
        continue;
      }

      // Run change state given parser, "done" and 0.
      parser.change_state(State::DONE, 0);
      // Break.
      break;
    }

    // If the result of running is a group open given parser is true: