computedWithControl

Usage

TypeScript

import { computedWithControl } from '@vueuse/core'

const source = ref('foo')
const counter = ref(0)

const computedRef = computedWithControl(
  () => source.value, // watch source, same as `watch`
  () => counter.value, // computed getter, same as `computed`
)

import { computedWithControl } from '@vueuse/core'
const source = ref('foo')
const counter = ref(0)
const computedRef = computedWithControl(
  () => source.value, // watch source, same as `watch`
  () => counter.value,
)

With this, the changes of counter won't trigger computedRef to update but the source ref does.

console.log(computedRef.value) // 0

counter.value += 1

console.log(computedRef.value) // 0

source.value = 'bar'

console.log(computedRef.value) // 1

Manual Triggering

You can also manually trigger the update of the computed by:

const computedRef = computedWithControl(
  () => source.value,
  () => counter.value,
)

computedRef.trigger()

Deep Watch

Unlike computed, computedWithControl is shallow by default. You can specify the same options as watch to control the behavior:

const source = ref({ name: 'foo' })

const computedRef = computedWithControl(
  source,
  () => counter.value,
  { deep: true },
)

Type Declarations

typescript

export interface ComputedWithControlRefExtra {
  /**
   * Force update the computed value.
   */
  trigger: () => void
}
export interface ComputedRefWithControl<T>
  extends ComputedRef<T>,
    ComputedWithControlRefExtra {}
export interface WritableComputedRefWithControl<T>
  extends WritableComputedRef<T>,
    ComputedWithControlRefExtra {}
export type ComputedWithControlRef<T = any> =
  | ComputedRefWithControl<T>
  | WritableComputedRefWithControl<T>
export declare function computedWithControl<T, S>(
  source: WatchSource<S> | WatchSource<S>[],
  fn: ComputedGetter<T>,
  options?: WatchOptions,
): ComputedRefWithControl<T>
export declare function computedWithControl<T, S>(
  source: WatchSource<S> | WatchSource<S>[],
  fn: WritableComputedOptions<T>,
  options?: WatchOptions,
): WritableComputedRefWithControl<T>
export { computedWithControl as controlledComputed }