taskify overview

Creates a new function that, when called, returns the same promise as the original function. If the returned function is called multiple times, it will always return the same promise, ensuring that the original function is only executed once.

Note that a task’s computation must not be able to fail.

Example

import { taskify } from '@dankreiger/puppy-fp'
;(async () => {
  const longRunning = () => new Promise((resolve) => setTimeout(resolve, 1000))
  const runTask = taskify(longRunning)
  const t0 = performance.now()
  await runTask()
  const t1 = performance.now()
  const duration1 = t1 - t0
  console.assert(duration1 >= 1000, { expect: 1000, actual: duration1 })
  await runTask()
  const t2 = performance.now()
  const duration2 = t2 - t1
  console.assert(duration2 === 100000, { expect: 1000, actual: duration2 })
})()

Added in v0.0.1

Table of contents

task

taskify

Creates a new function that, when called, returns the same promise as the original function. If the returned function is called multiple times, it will always return the same promise, ensuring that the original function is only executed once.

Note that a task’s computation must not be able to fail.

Signature

export declare function taskify<T>(fn: () => Promise<T>): () => Promise<T>

Example

import { taskify } from '@dankreiger/puppy-fp'
;(async () => {
  const longRunning = () => new Promise((resolve) => setTimeout(resolve, 1000))
  const runTask = taskify(longRunning)
  const t0 = performance.now()
  await runTask()
  const t1 = performance.now()
  const duration1 = t1 - t0
  console.assert(duration1 >= 1000, { expect: 1000, actual: duration1 })
  await runTask()
  const t2 = performance.now()
  const duration2 = t2 - t1
  console.assert(duration2 === 100000, { expect: 1000, actual: duration2 })
})()

Added in v0.0.1