Using uid_in to filter by two edges away?

Sorry, figured it out!

{
  var(func: uid(0xaf11)) {    
    has_pin {
      A as ~includes_pin
    }
  }
  routesWithinMap(func: uid(A)) {
    uid
    includes_pin {  # pins within this route
      ~has_pin {    # maps this pin belongs to
      	   uid      # as expected, this is always "0xaf11"
    	}
    }
  }
}