groupBy
Functions
groupBy()
groupBy<
T,U>(arrayOrPromise,callbackfn):Promise<Map<U,T[]>>
Groups the elements of an array based on the result of the callbackfn function.
Type Parameters
| Type Parameter |
|---|
T |
U |
Parameters
| Parameter | Type | Description |
|---|---|---|
arrayOrPromise | T[] | Promise<T[]> | The array or Promise of an array to iterate over. |
callbackfn | (value, index, array) => U | Promise<U> | A function that accepts up to three arguments. The groupBy method calls the callbackfn function one time for each element in the array. |
Returns
Promise<Map<U, T[]>>
A Promise that resolves with a Map containing the elements grouped by the key returned by the callbackfn function.