algebra.id(props)

Returns the configured id property value from props. If there are multiple ids, a JSON.stringify-ed JSON object is returned with each id value is returned.

var algebra1 = new set.Algebra(set.props.id("_id"));
algebra1.id({_id: 5}) //-> 5

var algebra2 = new set.Algebra(
  set.props.id("studentId"),
  set.props.id("classId")
);

algebra2.id({studentId: 6, classId: "7", foo: "bar"})
    //-> '{"studentId": 6, "classId": "7"}'