I realise I'm probably splitting hairs here, but I feel like there should be some sort of convention or best practice for this situation, but I haven't been able to find anything online, and I can't figure out what it should be.
I'm developing a rostering tool which produces a weekly calendar. The majority of the work assignments are for an entire week, so having a single cell to indicate that is both sufficient, and desirable from an information-density standpoint.
That being said, occasionally someone will be assigned somewhere for only part of a week, and it is necessary for this to be indicated on the calendar. The obvious solution is to simply include the days of the week in the cell, when it's a partial week assignment - for example, if the person is only working Monday to Thursday, it might say (M-Th), if they were working Monday, Wednesday & Friday, it'd say (M,W,F), if they were working every day except Thursday, it'd say (M-W,F), and so on.
The issue is how to deal with two-day work periods - if, for example, they're working on Monday and Tuesday, should it be (M,Tu) or (M-Tu)?
I can see arguments for both sides - on the one hand, the dash can be taken to indicate the elision of days for the sake of brevity (e.g. in the case "M-Th", where the dash takes the place of "Tu" and "W"); in which case, it should be "M,Tu", as there are no days between Monday and Tuesday that are being elided from the text.
On the other hand, the dash could be interpreted as an indication that the period being specified is continuous run of days, (i.e. "M-Th" indicates there are no gaps between M and Th) in which case it should be "M-Tu", as there is no gap between Monday and Tuesday.
Is there a standard for this? Is there something I've missed?