<A>(self: SubscriptionRef<A>): Effect.Effect<A>Retrieves the current value of the SubscriptionRef.
Example (Reading the current value)
import { Effect, SubscriptionRef } from "effect"
const program = Effect.gen(function*() {
const ref = yield* SubscriptionRef.make(42)
const value = yield* SubscriptionRef.get(ref)
console.log(value)
})export const const get: <A>(
self: SubscriptionRef<A>
) => Effect.Effect<A>
Retrieves the current value of the SubscriptionRef.
Example (Reading the current value)
import { Effect, SubscriptionRef } from "effect"
const program = Effect.gen(function*() {
const ref = yield* SubscriptionRef.make(42)
const value = yield* SubscriptionRef.get(ref)
console.log(value)
})
get = <function (type parameter) A in <A>(self: SubscriptionRef<A>): Effect.Effect<A>A>(self: SubscriptionRef<A>(parameter) self: {
value: A;
semaphore: Semaphore.Semaphore;
pubsub: PubSub.PubSub<A>;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
}
interface SubscriptionRef<in out A>A mutable reference whose updates are serialized and published to
subscribers.
When to use
Use to observe the current value and subsequent updates as a
stream.
The SubscriptionRef namespace containing type definitions associated with
subscription references.
SubscriptionRef<function (type parameter) A in <A>(self: SubscriptionRef<A>): Effect.Effect<A>A>): import EffectEffect.interface Effect<out A, out E = never, out R = never>The Effect interface defines a value that lazily describes a workflow or
job. The workflow requires some context R, and may fail with an error of
type E, or succeed with a value of type A.
When to use
Use when you need to represent a lazy, composable workflow that can require
services, fail with a typed error, or succeed with a typed value.
Details
Effect values model resourceful interaction with the outside world,
including synchronous, asynchronous, concurrent, and parallel interaction.
They use a fiber-based concurrency model, with built-in support for
scheduling, fine-grained interruption, structured concurrency, and high
scalability.
To run an Effect value, you need a Runtime, which is a type that is
capable of executing Effect values.
Effect<function (type parameter) A in <A>(self: SubscriptionRef<A>): Effect.Effect<A>A> => import EffectEffect.const sync: <A>(
thunk: LazyArg<A>
) => Effect<A>
Creates an Effect that represents a synchronous side-effectful computation.
When to use
Use when you need to wrap a synchronous side-effectful operation that is not
expected to throw.
Details
The provided function is evaluated lazily when the effect runs.
Gotchas
The function must not throw. If it throws, the thrown value is treated as a
defect, not as a typed failure. Use try when throwing is expected.
Example (Capturing synchronous logging in an Effect)
import { Effect } from "effect"
const log = (message: string) =>
Effect.sync(() => {
console.log(message) // side effect
})
// ┌─── Effect<void, never, never>
// ▼
const program = log("Hello, World!")
sync(() => self: SubscriptionRef<A>(parameter) self: {
value: A;
semaphore: Semaphore.Semaphore;
pubsub: PubSub.PubSub<A>;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
}
SubscriptionRef<A>.value: Avalue)