import type { Extended } from './isExtension.js';
export declare const $PREPEND: unique symbol;
export type $PREPEND = typeof $PREPEND;
export type PREPEND<VALUE> = Extended<{
    [$PREPEND]: VALUE;
}>;
export declare const $prepend: <VALUE>(value: VALUE) => PREPEND<VALUE>;
export declare const isPrepending: (input: unknown) => input is {
    [$PREPEND]: unknown;
};