int abx = 43; system.debug(abx);
Standard input is empty
Object: nil error: did not understand #abx MessageNotUnderstood(Exception)>>signal (ExcHandling.st:254) UndefinedObject(Object)>>doesNotUnderstand: #abx (SysExcept.st:1448) UndefinedObject>>executeStatements (prog:1)
./prog:2: expected expression