ISO-8601 EDTF Bat Signal!
I'm finding contradictory instructions on expressing a circa date range. As in "we don't know for sure when this was created, but based on other information we have, we're guessing between 1968 and 1971"
We used to use ~1968/~1971
But that seems to be superseded???
@metacat so it seems like it has to do with levels of implementation in system design. At some levels only some things are supported and at others more options are supported.
In the new one, I believe 1968~/1971~ would be valid, as would 1968?/1971? and 196X-197X... in Level 1... which is kind of not great because they all mean slightly different but also too-similar things.
Level 2 throws in the ability to add Xs anywhere, e.g. 1X68 (if it was a blurry number or something)
@platypus @metacat [just to add to the confusion a bit (sorry), Level 2 has “date sets” which seem semantically accurate to what you’re saying…
e.g. [1968..1971] means ”some (single) date between 1968 and 1971”. this differs from 1968/1971 which specifies the interval not a single date in the set.
does anybody actually use these though?? um, idk; our legacy system was also 1968~/1972~ and we’re still trying to figure out how we want to handle those in the replacement
i personally wouldn't worry too much about the levels; i think in practice what a technology does/does not support will probably not align with the level distinctions made in the spec]
