Follow one execution
Both subscriptions run together; every value is forwarded and completion waits for both.
mergeTick 0. Local: local-1; Output: local-1.
Read this diagram
Follow each lane from left to right. Events stacked vertically share a tick; the green cursor marks the current time across every lane.
- A value
The text inside the pill is the emitted value. - Work starts
The raised chevron starts an inner run (^in the source). - The run returns
The vertical bar ends this lane’s run. - A cause is delivered
The exclamation mark belongs to this lane. - Work is interrupted
The cross marks cancellation of this run. - Current time
The line and diamond move together across all lanes. - Happening now
A highlighted event is at the current tick. - Still ahead
Muted, dashed values have not happened yet. - Time continues
The lane’s arrow is not a return marker. An empty stretch can be quiet work that is still running.
Illustrated ticks start at 0. At 1×, one illustrated tick takes one second; captions specify real durations when timing matters. A cause or interruption belongs to its lane, and other work may continue. Scroll horizontally to inspect the rest of a long timeline.
Both runs are children of the consumer and completion waits for both. Downstream interruption cancels the remaining runs. A source Cause is only sent to sink.onFailure; whether that callback ends observation is Sink policy, not an intrinsic terminal rule of merge.
Import
import { merge } from "@typed/fx/Fx";Signatures
export declare const merge: {
<A2, E2, R2>(that: Fx<A2, E2, R2>): <A, E, R>(self: Fx<A, E, R>) => Fx<A | A2, E | E2, R | R2>;
<A, E, R, A2, E2, R2>(self: Fx<A, E, R>, that: Fx<A2, E2, R2>): Fx<A | A2, E | E2, R | R2>;
};Why
merge preserves both producers instead of imposing a pairing relationship. Each input value is
emitted once as soon as its source pushes it, so inter-source ordering is intentionally undefined.
Ownership and lifetime
Both runs are children of the consumer and completion waits for both. Downstream interruption
cancels the remaining runs. A source Cause is only sent to sink.onFailure; whether that callback
ends observation is Sink policy, not an intrinsic terminal rule of merge.
Examples
import { Effect, Ref } from "effect"
import { Fx, Sink } from "@typed/fx"
const program = Effect.gen(function* () {
const deliveries = yield* Ref.make<Array<string>>([])
const sink = Sink.make(
() => Ref.update(deliveries, (xs) => [...xs, "failure"]),
(value: string) => Ref.update(deliveries, (xs) => [...xs, value])
)
yield* Fx.merge(Fx.fail("left failed"), Fx.succeed("right continued")).run(sink)
return yield* Ref.get(deliveries) // both "failure" and "right continued"
})Other public imports
These import paths expose the same declaration. Each page retains its own public name and signature.