useGroupBy; initialState.groupBy; How to group by accessor.nestedKey instead of accessor itself?

[sthtnr]

I want to know how to group by a deeper hierarchy of key that accessor accesses, rather than by the value of accessor itself.
For example, suppose we have the following data:

let user = [
{
  "name": {
    "first": "aaa",
    "last": "bbb"
  },
  "age": 20
},
...
]

And if I set name as first column's accessor, Is it possible to group by name.first with initialState.groupBy?
I tried like the following, but it didn't work.

initialState: {groupBy: ['name.first']}

initialState: {groupBy: [columns[0].accessor.first]}

I know I can accomplish to set name.first as accessor, but can't I accomplish this without doing so?

[gargroh]

Any operation like sort, filter or group will take place on accessor only, you can use Cell to format or show something else in display.

[sthtnr]

I see, understood. Thanks for your answer.