it seems like CURIEs are currently mapped to XML as namespaces. that is good in principle, but sadly HAL's CURIEs aren't actually CURIEs. specifically, while CURIEs indeed just associate a prefix with a URI (just like namespaces), HAL uses a template mechanism. this is not something namespaces can do, so probably it would be better to represent CURIEs via XML markup and not as XML namespaces.