import { SelectorsCache } from '@state-adapt/core';
import { StoreLike } from '@state-adapt/rxjs';
/**
 * A shared, memoized value created with {@link derive}. Call it for its current
 * value, or pass it to {@link useDerived}.
 *
 * @hidden
 */
export interface Derived<Value> {
    (): Value;
    /** @internal */
    __: {
        fullSelector: (globalState?: any, cache?: SelectorsCache) => Value;
    };
}
export interface DerivedConsumer {
    consume(store: StoreLike<any, any, any>): void;
}
export declare const withDerivedConsumer: <Value>(consumer: DerivedConsumer, read: () => Value) => Value;
export declare const createStoreSelectorReader: (store: StoreLike<any, any, any>, fullSelector: (globalState: any, cache?: SelectorsCache) => any, isUnavailable?: () => boolean) => () => any;
/**
 * Creates a shared, memoized value derived from stores created with
 * {@link adapt}. Call it for its current value, or subscribe a component to it
 * with {@link useDerived}.
 *
 * Define it outside your components:
 *
 * ```tsx
 * import { adapt, derive, useDerived } from '@state-adapt/react';
 *
 * const priceStore = adapt(20);
 * const quantityStore = adapt(3);
 *
 * const deriveSubtotal = derive(() => priceStore() * quantityStore());
 * const deriveTotal = derive(() => deriveSubtotal() + 5);
 *
 * function Total() {
 *   const total = useDerived(deriveTotal);
 *
 *   return <p>Total: {total}</p>;
 * }
 * ```
 */
export declare function derive<Value>(projector: () => Value): Derived<Value>;