(Digester) Namespace logic

[robert burrell donkin]

(you might have guessed that i'm working on test cases...)

i'm a little confused about the (intended) matching rules namespace logic.
i'd say that the current behaviour is probably not correct - but maybe 
that's what's intended :)

should a rule with a null namespace be matched when a non-null namespace 
is passed in? in other words does a null namespace for a rule imply that 
it matches only elements without a namespace or does a null namespace 
match any namespace. (of course, this is assuming that the rule would 
qualify otherwise)


if i know which is correct i can prepare documentation patches and a code 
patch (if that's needed).
(this is easy for me to do at the moment since i'm trying to prepare a 
separate (and extended) test case RulesBase which can be extended to act 
as a basis for testing extensions of RulesBase)

- robert