I'd like to propose adding a %W identifier to the XPath functions format-date() and format-date-time() to return the week number as specified under ISO 8601.
The %W identifier was copied from an another implementation in Python.
This is a sample JS implementation: https://www.epoch-calendar.com/support/getting_iso_
Some Enketo users have expressed interest in this functionality. It is relatively minor and probably not controversial.
That sounds good to me! My preference would be to base it off XPath 3.1 which by default outputs an integer. The Python function you point to outputs a 0-padded 2-digit decimal.
Ah, I forgot to look at XPath specs... Thank you! I agree to use that as that as the spec for this %W identifier addition.
FWIW, I likewise agree with proposal, and using XPath 3.1 spec thereof.
Filed at https://github.com/opendatakit/xforms-spec/issues/265 since there have been no objections and when a feature comes from an existing spec we usually go straight ahead.
Very useful would love to see it.