Easier way to handle exceptions instead of try/catch every line?

[dominique120]

Hi,

I'm wondering if there is a better way of handling exceptions in a situation like this:

	profile.url = j.at("url").get<std::string>();
	profile.created_at = j.at("created_at").get<std::string>();
	profile.name = j.at("name").get<std::string>();
	profile.username = j.at("username").get<std::string>();

Since I cant guarantee that all the lines will be strings(might be null, etc) is there a way for them to fallback to just returning an empty string or json null, instead of having to wrap each line in a try/catch block?

Thanks!

[nlohmann]

If you know the value is either null or a string, then you can use the value function. Note it throws if the actual value is not null, but does not fit the default value. If you cannot rule out such situations, I guess the best would be a helper function. Something like

std::string get_value(const json& j, const std::string& key, const std::string& default_value)
{
	if (j.contains("key") && j["key"].is_string())
	{
		return j["key"];
	}
	return default_value;
}

[dominique120]

Yeah that works for me. I dont even know if the value will even be there but this gives me some ideas of how to handle it. Thanks!