should make-element default to the default namespace or ""?

[slyrus]

Currently, if we do:

(let ((foo (fxml.stp:make-element "foo" "http://foo.example.com")))
  (fxml.stp:append-child
   foo
   (let ((element (fxml.stp:make-element "BarElement")))
     (setf (fxml.stp:attribute-value element "firstAttribute") "works")
     element))
  (let ((doc (fxml.stp:make-document foo)))
    (fxml.stp:serialize
     doc
     (fxml:make-character-stream-sink *standard-output* :indentation 2))))

We get a namespace of xmlns="" in the BarElement definition. I was hoping to just not have an xmlns attribute, meaning that the definition of BarElement would pick up the default namespace (http://foo.example.com). In order to get that behavior I have to explicitly provide the uri. Is this the expected/intended behavior?

[ruricolist]

I'll have to do some research first to make sure this isn't what XML mandates.

[slyrus]

I'd argue that XML doesn't mandate anything about how are API works. But the parallel with XML is that if we don't specify and xmlns, we pick up the current default. Whereas our API results in not specifying an xmlns yielding xmlns="". But if were to implement things as I suggested, it would mean that the actual xmlns of an element wouldn't be known until the default namespace was known, that is to say that if you make some nodes and move them around, the actual NS could change. I can see arguments for both kinds of behaviors, but the current one seems a bit unintuitive to me.