/** @module array/flattenOnceArray.ts */
import { BasicTypes, FlattenArray, FlattenOnce } from '../helper-types';
declare function flattenOnceArray<A extends BasicTypes, B extends [A, ...A[]], C extends [B, ...B[]], D extends [C, ...C[]], E extends [D, ...D[]], F extends [E, ...E[]], G extends [F, ...F[]], H extends [G, ...G[]], I extends [H, ...H[]], J extends [I, ...I[]], K extends [J, ...J[]], L extends [K, ...K[]], M extends [L, ...L[]], N extends [M, ...M[]], O extends [N, ...N[]], P extends [O, ...O[]], Q extends [P, ...P[]], Narrow extends [(A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P), ...Array<A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P>]>(arr: Narrow): FlattenOnce<Narrow>;
declare function flattenOnceArray<A extends [any, ...any[]]>(arr: A): FlattenOnce<A>;
declare function flattenOnceArray<A extends Array<unknown>>(arr: A): FlattenArray<A>;
export default flattenOnceArray;