Function rollup

rollup<TObject, TReduce, TKeys>(iterable, reduce, ...keys): NestedInternMap<TObject, TReduce, TKeys>
Groups and reduces the specified array of values into an InternMap from key to value.
Type Parameters
- TObject
- TReduce
- TKeys extends unknown[]
Parameters
- iterable: Iterable<TObject>
  The iterable to group.
- reduce: ((values) => TReduce)
  The reduce function.
  - - (values): TReduce
    - Parameters
      values: TObject[]
      Returns TReduce
- Rest ...keys: {
  [Index in string | number | symbol]: ((value, index, values) => TKeys[Index])
  }
  The key functions.
Returns NestedInternMap<TObject, TReduce, TKeys>