Function default_val

include/CLI/Option.hpp:817–847

    /// Set the default value and validate the results and run the callback if appropriate to set the value into the
    /// bound value only available for types that can be converted to a string
    template <typename X> Option *default_val(const X &val) {
        std::string val_str = detail::value_string(val);
        auto old_option_state = current_option_state_;
        results_t old_results{std::move(results_)};
        results_.clear();
        try {
            add_result(val_str);
            // if trigger_on_result_ is set the callback already ran
            if(run_callback_for_default_ && !trigger_on_result_) {
                run_callback();  // run callback sets the state, we need to reset it again
                current_option_state_ = option_state::parsing;
            } else {
                _validate_results(results_);
                current_option_state_ = old_option_state;
            }
        } catch(const ConversionError &err) {
            // this should be done
            results_ = std::move(old_results);
            current_option_state_ = old_option_state;

            throw ConversionError(
                get_name(), std::string("given default value(\"") + val_str + "\") produces an error : " + err.what());
        } catch(const CLI::Error &) {
            results_ = std::move(old_results);
            current_option_state_ = old_option_state;
            throw;
        }
        results_ = std::move(old_results);
        default_str_ = std::move(val_str);
        return this;
    }

    /// Get the full typename for this option
    CLI11_NODISCARD std::string get_type_name() const;