effect-io-ai

Package: effect
Module: TxSubscriptionRef

TxSubscriptionRef.TxSubscriptionRef

A TxSubscriptionRef is a transactional reference that allows subscribing to all committed changes. Subscribers receive the current value followed by every subsequent update via a transactional dequeue.

When to use

Use to store transactional state whose committed changes must be observable by subscribers.

Example (Subscribing to transactional changes)

import { Effect, TxQueue, TxSubscriptionRef } from "effect"

const program = Effect.gen(function*() {
  const ref = yield* TxSubscriptionRef.make(0)

  yield* Effect.scoped(
    Effect.gen(function*() {
      const sub = yield* TxSubscriptionRef.changes(ref)
      const initial = yield* TxQueue.take(sub)
      console.log(initial) // 0

      yield* TxSubscriptionRef.set(ref, 1)
      const next = yield* TxQueue.take(sub)
      console.log(next) // 1
    })
  )
})

See

• make for creating a transactional subscription reference
• changes for subscribing through a transactional queue
• changesStream for subscribing through a Stream

Signature

export interface TxSubscriptionRef<in out A> extends Inspectable, Pipeable {
  readonly [TypeId]: typeof TypeId
  /** @internal */
  readonly ref: TxRef.TxRef<A>
  /** @internal */
  readonly pubsub: TxPubSub.TxPubSub<A>
}

Source

Since v4.0.0