A matrix or dataframe, for example. But as I said, Tables.jl doesn’t support mutating sources yet, so TableView.jl can’t either. @quinnj (or maybe @piever) probably knows how realistic it is to get that anytime soon.
It would be fairly trivial to do this for some tables, probably, but I’d really like to avoid special casing e.g. DataFrames (and depending on it, of course).
One thing we could also do is add a callback kwarg to showtable, which has the edited cell and the new value as its arguments. That would put the burden of figuring out how to mutate the table on you though
Yeah, there’s an open issue about this for Tables.jl. Part of the issue is that there is indeed a ton of variability in terms of which tables could support this; pretty much only in-memory sources, which would exclude file formats (feather, csv), most databases (sqlite, mysql, odbc), so it just hasn’t felt like a high priority given this would be exclusively for in-memory structures.
There was talk at one point of possibly enhancing or creating a new InMemoryTable interface that could add additional features like: mutability, requiring getindex and iteration on rows, etc.