Returns an effect that forks this effect into its own separate fiber, returning the fiber immediately, without waiting for it to begin executing the effect.

Details

You can use the forkChild method whenever you want to execute an effect in a new fiber, concurrently and without "blocking" the fiber executing other effects. Using fibers can be tricky, so instead of using this method directly, consider other higher-level methods, such as raceWith, zipPar, and so forth.

The fiber returned by this method has methods to interrupt the fiber and to wait for it to finish executing the effect. See Fiber for more information.

Whenever you use this method to launch a new fiber, the new fiber is attached to the parent fiber's scope. This means when the parent fiber terminates, the child fiber will be terminated as well, ensuring that no fibers leak. This behavior is called "auto supervision", and if this behavior is not desired, you may use the forkDetach or forkIn methods.

Example (Forking a child fiber)

import { Effect, Fiber } from "effect"

const longRunningTask = Effect.gen(function*() {
  yield* Effect.sleep("2 seconds")
  yield* Effect.log("Task completed")
  return "result"
})

const program = Effect.gen(function*() {
  const fiber = yield* longRunningTask.pipe(Effect.forkChild)

  // or fork a fiber that starts immediately:
  yield* longRunningTask.pipe(Effect.forkChild({ startImmediately: true }))

  yield* Effect.log("Task forked, continuing...")
  const result = yield* Fiber.join(fiber)
  return result
})