@kevinswiber  You mean an api request with a fragment?  Does that mean the response is just the customerInfo sub-entity?  

On the client side I believe I'm with @dilvie that `class` works well enough but a concrete example would help me tremendously.  In the mean time, if you have the *id* as a property of the entity couldn't you select all sub-entities and then filter on the *id* property?

I've never been a fan of the '#ID' style of selection.  I prefer to select items generically and filter on known properties.  Sort of like jquery style where all selection results are an array regardless if there are 0 or more results.