deferred class B feature {NONE} -- Tests e1 require is_empty: ("").is_empty external "C inline" alias "return" ensure different: "" /= "" end e2 require is_empty: ("").is_empty external "C inline" alias "return" ensure different: "" /= "" end o1 require is_empty: ("").is_empty once ("OBJECT") ensure different: "" /= "" end o2 require is_empty: ("").is_empty once ("OBJECT") ensure different: "" /= "" end p1 require is_empty: ("").is_empty do ensure different: "" /= "" end p2 require is_empty: ("").is_empty do ensure different: "" /= "" end p3 require is_empty: ("").is_empty deferred ensure different: "" /= "" end end