effect-io-ai

Package: effect
Module: Effect

Effect.zip

Combines two effects into a single effect, producing a tuple with the results of both effects.

When to use

Use to combine exactly two effects into a tuple.

Details

The zip function executes the first effect (left) and then the second effect (right). Once both effects succeed, their results are combined into a tuple.

Concurrency:

By default, zip processes the effects sequentially. To execute the effects concurrently, use the { concurrent: true } option.

Example (Combining two effects sequentially)

import { Effect } from "effect"

const task1 = Effect.succeed(1).pipe(
  Effect.delay("200 millis"),
  Effect.tap(Effect.log("task1 done"))
)
const task2 = Effect.succeed("hello").pipe(
  Effect.delay("100 millis"),
  Effect.tap(Effect.log("task2 done"))
)

// Combine the two effects together
//
//      ┌─── Effect<[number, string], never, never>
//      ▼
const program = Effect.zip(task1, task2)

Effect.runPromise(program).then(console.log)
// Output:
// timestamp=... level=INFO fiber=#0 message="task1 done"
// timestamp=... level=INFO fiber=#0 message="task2 done"
// [ 1, 'hello' ]

Example (Combining two effects concurrently)

import { Effect } from "effect"

const task1 = Effect.succeed(1).pipe(
  Effect.delay("200 millis"),
  Effect.tap(Effect.log("task1 done"))
)
const task2 = Effect.succeed("hello").pipe(
  Effect.delay("100 millis"),
  Effect.tap(Effect.log("task2 done"))
)

// Run both effects concurrently using the concurrent option
const program = Effect.zip(task1, task2, { concurrent: true })

Effect.runPromise(program).then(console.log)
// Output:
// timestamp=... level=INFO fiber=#0 message="task2 done"
// timestamp=... level=INFO fiber=#0 message="task1 done"
// [ 1, 'hello' ]

See

• zipWith for a version that combines the results with a custom function.
• all for collecting a larger structure of effects.

Signature

declare const zip: { <A2, E2, R2>(that: Effect<A2, E2, R2>, options?: { readonly concurrent?: boolean | undefined; } | undefined): <A, E, R>(self: Effect<A, E, R>) => Effect<[A, A2], E2 | E, R2 | R>; <A, E, R, A2, E2, R2>(self: Effect<A, E, R>, that: Effect<A2, E2, R2>, options?: { readonly concurrent?: boolean | undefined; }): Effect<[A, A2], E | E2, R | R2>; }

Source

Since v2.0.0