Function groupBy

groupBy<T extends XNode | XAttribute, K>(
items: T[],
keySelector: (item: T) => K,
): Map<K, XSequence<T>>
Groups the items by a key derived from each item.
Type Parameters
- T extends XNode | XAttribute
  The element type.
- K
  The type of the grouping key.
Parameters
- items: T[]
  The items to group.
- keySelector: (item: T) => K
  A function that returns the grouping key for each item.
Returns Map<K, XSequence<T>>
A map from each key to an XSequence of its matching items.
- Defined in src/XSequence.ts:511