A shell in Rust could be really cool

Sounds like dates in Excel. If you paste *text* into a cell, and then try to interpret it as a date, it barfs when fed a "wrong" date. I've just yesterday had to fix that problem ...

Copy a column of date-times from one spreadsheet to another. Format the date-time as a time. Save as a csv. If you're not in America the csv will contain a "random" mix of times and date-times. But all the date-times will not be a valid American date, for example today - 15/02/2025 - will be a date-time, while fast-forward a fortnight to 01/03/2025 and it will be correctly converted to a time.

The fix is easy - explicitly format/force the text into a European date, and everything then works, but it's a pain in the arse. Especially if every time you hit the problem, you've forgotten the previous time ...

Cheers,
Wol