[rules-users] suggestion for drl grammar: single-element constraints

If a fact contains a single field, it would be nice to be able to express a constraint on the value of that field without having to know its name, e.g.: Cheese ("stilton") which would be equivalent to Cheese (type == "stilton") if Cheese contained only one field, and which would be a compile-time error otherwise. A similar convenience syntax is used, for instance, for Java 5 annotations. Instead of having to say @Retention(value = RetentionPolicy.RUNTIME) it can be abbreviated @Retention(RetentionPolicy.RUNTIME) since this annotation only has a single field. - Godmar