Function: flatMap()
flatMap<
ElementType,MappedType>(iterable:IterableResolvable<ElementType>,callbackFn: (element:ElementType,index:number) =>IterableResolvable<MappedType>):IterableIterator<MappedType>
Defined in: projects/utilities/packages/iterator-utilities/src/lib/flatMap.ts:21
Creates an iterable that yields the elements of each iterable returned by the provided function on each element of the input iterable.
Type Parameters
| Type Parameter |
|---|
ElementType |
MappedType |
Parameters
| Parameter | Type | Description |
|---|---|---|
iterable | IterableResolvable<ElementType> | An iterator to map. |
callbackFn | (element: ElementType, index: number) => IterableResolvable<MappedType> | A function to execute for each element produced by the iterator. It should return an iterator or iterable that yields elements to be yielded by flatMap(), or a single non-iterator/iterable value to be yielded. |
Returns
IterableIterator<MappedType>
An iterator that applies a function to each element of the input iterator and yields the results.
Example
import { flatMap } from '@sapphire/iterator-utilities';
const iterable = [1, 2, 3];
console.log([...flatMap(iterable, (value) => [value, value * 2])]);
// Output: [1, 2, 2, 4, 3, 6]