until

类别

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导出体积

595 B

上次更改

3 minutes ago

等待变化的一次性 Promise

示例

源码

将计数增加到 7 以显示警报。

计数: 0

用法

等待一些异步数据准备就绪

import { until, useAsyncState } from '@vueuse/core'

const { state, isReady } = useAsyncState(
  fetch('https://jsonplaceholder.typicode.com/todos/1').then(t => t.json()),
  {},
)

;(async () => {
  await until(isReady).toBe(true)

  console.log(state) // 状态现在已经准备就绪！
})()

等待自定义条件

你可以使用 invoke 调用异步函数。

import { invoke, until, useCounter } from '@vueuse/core'

const { count } = useCounter()

invoke(async () => {
  await until(count).toMatch(v => v > 7)

  alert('计数器现在大于 7!')
})

超时

// 将会在 ref.value === true 或者 1000ms 过去时解析
await until(ref).toBe(true, { timeout: 1000 })

// 如果超时将会抛出错误
try {
  await until(ref).toBe(true, { timeout: 1000, throwOnTimeout: true })
  // ref.value === true
}
catch (e) {
  // 超时
}

类型声明

显示类型声明

typescript

export interface UntilToMatchOptions {
  /**
   * 当条件未满足时，Promise resolve/reject 的毫秒超时时间。
   * 0 表示永不超时
   *
   * @default 0
   */
  timeout?: number
  /**
   * 当超时时是否拒绝 Promise
   *
   * @default false
   */
  throwOnTimeout?: boolean
  /**
   * 内部监视的 `flush` 选项
   *
   * @default 'sync'
   */
  flush?: WatchOptions["flush"]
  /**
   * 内部监视的 `deep` 选项
   *
   * @default 'false'
   */
  deep?: WatchOptions["deep"]
}
export interface UntilBaseInstance<T, Not extends boolean = false> {
  toMatch: (<U extends T = T>(
    condition: (v: T) => v is U,
    options?: UntilToMatchOptions,
  ) => Not extends true ? Promise<Exclude<T, U>> : Promise<U>) &
    ((
      condition: (v: T) => boolean,
      options?: UntilToMatchOptions,
    ) => Promise<T>)
  changed: (options?: UntilToMatchOptions) => Promise<T>
  changedTimes: (n?: number, options?: UntilToMatchOptions) => Promise<T>
}
type Falsy = false | void | null | undefined | 0 | 0n | ""
export interface UntilValueInstance<T, Not extends boolean = false>
  extends UntilBaseInstance<T, Not> {
  readonly not: UntilValueInstance<T, Not extends true ? false : true>
  toBe: <P = T>(
    value: MaybeRefOrGetter<P>,
    options?: UntilToMatchOptions,
  ) => Not extends true ? Promise<T> : Promise<P>
  toBeTruthy: (
    options?: UntilToMatchOptions,
  ) => Not extends true ? Promise<T & Falsy> : Promise<Exclude<T, Falsy>>
  toBeNull: (
    options?: UntilToMatchOptions,
  ) => Not extends true ? Promise<Exclude<T, null>> : Promise<null>
  toBeUndefined: (
    options?: UntilToMatchOptions,
  ) => Not extends true ? Promise<Exclude<T, undefined>> : Promise<undefined>
  toBeNaN: (options?: UntilToMatchOptions) => Promise<T>
}
export interface UntilArrayInstance<T> extends UntilBaseInstance<T> {
  readonly not: UntilArrayInstance<T>
  toContains: (
    value: MaybeRefOrGetter<ElementOf<ShallowUnwrapRef<T>>>,
    options?: UntilToMatchOptions,
  ) => Promise<T>
}
/**
 * 等待变化的一次性 Promise
 *
 * @see https://vueuse.org/until
 * @example
 * ```
 * const { count } = useCounter()
 *
 * await until(count).toMatch(v => v > 7)
 *
 * alert('计数器现在大于 7!')
 * ```
 */
export declare function until<T extends unknown[]>(
  r: WatchSource<T> | MaybeRefOrGetter<T>,
): UntilArrayInstance<T>
export declare function until<T>(
  r: WatchSource<T> | MaybeRefOrGetter<T>,
): UntilValueInstance<T>