Please provide a method to deserialize and discard one object

[joshtriplett]

For resilient parsing of CBOR streams that may contain unknown objects, I'd love to have a Deserializer method that parses and discards one CBOR object, including any contained objects. For instance, if the next object is a definite array, it'll parse and discard len objects; if the next object is an indefinite map, it'll parse and discard pairs of objects until it parses and discards a Break. This makes it easy to, for instance, discard the value associated with an unknown key in a map, allowing for extensible objects.