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flattenDeep (Functional Programming) ​

Creates a function that recursively flattens nested arrays. Use it with pipe.

typescript
const result = pipe(array, flattenDeep());

INFO

Prefer the original es-toolkit flattenDeep in ordinary code. Use this fp variant when composing transformations with pipe.

Usage ​

flattenDeep recursively removes every nested array layer from the piped array. It is lazy-capable inside pipe.

typescript
import { flattenDeep, pipe } from 'es-toolkit/fp';

pipe([1, [2, [3, [4]]]], flattenDeep()); // => [1, 2, 3, 4]

Parameters ​

This function takes no arguments; call it as flattenDeep().

Returns ​

((array: readonly T[]) => Array<ExtractNestedArrayType<T>>): A function that maps a nested array to a deeply flattened array.

Released under the MIT License.