Following up on what Deyja said: the template could (if I'm not smoking anything) also be disambiguated by assigning to a temporary, like this:

int w = config["width"];int h = config["height"];SetVideo(w, h);

Or you could (again, unless I'm smoking something) make the operator[] take a second dummy parameter of the required type, like this:

template<class T> const T& Config::operator[] (const string &name, T dummy) {  std::string result = mReader[name];  if(result.empty()) return StringTo<T>(mDefaults[name]);  return StringTo<T>(result);}// The "int(0)"s here should provide anonymous, auto storage ints.// But I'm not sure you can really do that...SetVideo(config["width", int(0)], config["height", int(0)]);

Or you could cause the Config class to maintain the association between key names and types... although I can't think of a way to do that without RTTI :s

Zahlman, I don't think that you first suggestion works at all. If I try something like that, I only get that there is no such function. That is, you need to use syntax that Deyja showed. However, I think that your second suggestion would work. I've actually been thinking about it myself, but that would actually make it longer. But thanks for the suggestions.