Stream: conformance
Topic: Multiple Extensions with same URL
Pascal Pfiffner (Apr 21 2020 at 05:47):
We don't explicitly state whether it's illegal or allowed to have multiple extensions with the same URL on an element anywhere on http://build.fhir.org/extensibility.html AFAICT. Am I missing it (and which is it)?
Vassil Peytchev (Apr 21 2020 at 13:10):
Given the language in the Notes I expect to have a unique URL per extension. If your question is whether an extension can be reused, I think the answer is yes - from the example of a Citizenship extension, you can have multiple citizenship, and therefore multiple extensions on the same patient.
Lloyd McKenzie (Apr 21 2020 at 13:53):
The number of repetitions permitted is determined by the cardinality at the root of the extension definition. Extensions that are allowed to repeat can absolutely have multiple occurrences in an instances with the same URL. While it's nice if they're grouped together, nothing stops them from being intermixed with other extensions.
Pascal Pfiffner (Apr 21 2020 at 18:02):
Aaah, thank you both; yes Vassil, that was exactly the question I was asking, and thanks Lloyd, I now see the root cardinality in the registry. :+1:🏼
Last updated: Apr 12 2022 at 19:14 UTC
