(, , , ..), _.set:
var data = {"prop.health": 1, "prop.cost":1, "prop.time":1};
_.each(data, function (value, key) {
delete data[key];
_.set(data, key, value);
});
_.set , . :
{"prop":{"health":1,"cost":1,"time":1}}
{"prop.health": 1, "prop.cost.food":1, "prop.time":1} :
{"prop":{"health":1,"cost":{"food":1},"time":1}}