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The React Framework

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import type { SchedulerFn } from './scheduler'; type CacheKeyFn<K, C extends string | number | null> = (key: K) => PromiseLike<C> | C; type BatcherOptions<K, C extends string | number | null> = { cacheKeyFn?: CacheKeyFn<K, C>; schedulerFn?: SchedulerFn<void>; }; type WorkFn<V, C> = (key: C, resolve: (value: V | PromiseLike<V>) => void) => Promise<V>; /** * A wrapper for a function that will only allow one call to the function to * execute at a time. */ export declare class Batcher<K, V, C extends string | number | null> { private readonly cacheKeyFn?; /** * A function that will be called to schedule the wrapped function to be * executed. This defaults to a function that will execute the function * immediately. */ private readonly schedulerFn; private readonly pending; protected constructor(cacheKeyFn?: CacheKeyFn<K, C> | undefined, /** * A function that will be called to schedule the wrapped function to be * executed. This defaults to a function that will execute the function * immediately. */ schedulerFn?: SchedulerFn<void>); /** * Creates a new instance of PendingWrapper. If the key extends a string or * number, the key will be used as the cache key. If the key is an object, a * cache key function must be provided. */ static create<K extends string | number | null, V>(options?: BatcherOptions<K, K>): Batcher<K, V, K>; static create<K, V, C extends string | number | null>(options: BatcherOptions<K, C> & Required<Pick<BatcherOptions<K, C>, 'cacheKeyFn'>>): Batcher<K, V, C>; /** * Wraps a function in a promise that will be resolved or rejected only once * for a given key. This will allow multiple calls to the function to be * made, but only one will be executed at a time. The result of the first * call will be returned to all callers. * * @param key the key to use for the cache * @param fn the function to wrap * @returns a promise that resolves to the result of the function */ batch(key: K, fn: WorkFn<V, C>): Promise<V>; } export {};