I think it would be useful to have an “as of” date modifier, expecially for occupation and residence events. Sometimes, we know when people moved at some place but most of the time, we know it from documents that at a certain point they would live there. The same is true for occupation.
I would also use that for association as I often find in the documents that people were neighbor at a certain time. And I would find it a pretty basic information to say someone was a forster parent from a certain day. But I’m surprised there’s no date field in the Associations…
It sounds like there are two different use cases here. One is a date span with a known begin date and an unknown end date, the other is a date span with unknown begin and end dates but a known date within the span.
I should probably have made 2 different topics but as I was wondering about “as of”, I thought it would also very much make sense for certain types of associations. But then I realised there was no date field for associations (hence “+ association date”), where different type of dates would be useful for different types of associations.
I can see the need for a way to aggregate events such as residence and occupation. If you have multiple sources that indicate that a person has lived in the same house at different times, then it may be reasonable to conclude that this is a single residence where we just know a few dates rather than specific start and end dates.
I think that sub-events would be a neat solution. An event could derive a date range from the dates of its sub-events.
Another idea would be to allow multiple dates in events, each with its own source citation.
When recently looking at the Timeline feature in another programs, they also do not aggregate and mentioned a reason to NOT do so.
Just because the same place is given on 2 census forms a decade apart does NOT definitively mean the person did not have another residence in between. Retirees might winter in a different part of the world. Or they might have moved back home just in time for the next census. And your research simply doesn’t yet have the date data resolution needed to show the other residences.
I also like the idea of a “by date” or “as of date” but since the date ranges of GEDCOM7 doesn’t include the subtlety of a qualifier like this, it doesn’t seem wise to introduce such a basic incompatibility.