<R>(context: Context.Context<R>): <A, E>(
effect: Effect<A, E, R>,
options?: RunOptions | undefined
) => Promise<Exit.Exit<A, E>>Runs an effect and returns a Promise of Exit with provided services.
When to use
Use when you already have a Context and need Promise interop that preserves
success and failure as an Exit.
Example (Running with services as an Exit promise)
import { Context, Effect, Exit } from "effect"
interface Database {
query: (sql: string) => string
}
const Database = Context.Service<Database>("Database")
const services = Context.make(Database, {
query: (sql) => `Result for: ${sql}`
})
const program = Effect.gen(function*() {
const db = yield* Database
return db.query("SELECT * FROM users")
})
Effect.runPromiseExitWith(services)(program).then((exit) => {
if (Exit.isSuccess(exit)) {
console.log("Success:", exit.value)
}
})export const const runPromiseExitWith: <R>(
context: Context.Context<R>
) => <A, E>(
effect: Effect<A, E, R>,
options?: RunOptions | undefined
) => Promise<Exit.Exit<A, E>>
Runs an effect and returns a Promise of Exit with provided services.
When to use
Use when you already have a Context and need Promise interop that preserves
success and failure as an Exit.
Example (Running with services as an Exit promise)
import { Context, Effect, Exit } from "effect"
interface Database {
query: (sql: string) => string
}
const Database = Context.Service<Database>("Database")
const services = Context.make(Database, {
query: (sql) => `Result for: ${sql}`
})
const program = Effect.gen(function*() {
const db = yield* Database
return db.query("SELECT * FROM users")
})
Effect.runPromiseExitWith(services)(program).then((exit) => {
if (Exit.isSuccess(exit)) {
console.log("Success:", exit.value)
}
})
runPromiseExitWith: <function (type parameter) R in <R>(context: Context.Context<R>): <A, E>(effect: Effect<A, E, R>, options?: RunOptions | undefined) => Promise<Exit.Exit<A, E>>R>(
context: Context.Context<R>(parameter) context: {
mapUnsafe: ReadonlyMap<string, any>;
mutable: boolean;
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; <…;
toString: () => string;
toJSON: () => unknown;
}
import ContextContext.type Context.Context = /*unresolved*/ anyContext<function (type parameter) R in <R>(context: Context.Context<R>): <A, E>(effect: Effect<A, E, R>, options?: RunOptions | undefined) => Promise<Exit.Exit<A, E>>R>
) => <function (type parameter) A in <A, E>(effect: Effect<A, E, R>, options?: RunOptions | undefined): Promise<Exit.Exit<A, E>>A, function (type parameter) E in <A, E>(effect: Effect<A, E, R>, options?: RunOptions | undefined): Promise<Exit.Exit<A, E>>E>(effect: Effect<A, E, R>(parameter) effect: {
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; <…;
toString: () => string;
toJSON: () => unknown;
}
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, E>(effect: Effect<A, E, R>, options?: RunOptions | undefined): Promise<Exit.Exit<A, E>>A, function (type parameter) E in <A, E>(effect: Effect<A, E, R>, options?: RunOptions | undefined): Promise<Exit.Exit<A, E>>E, function (type parameter) R in <R>(context: Context.Context<R>): <A, E>(effect: Effect<A, E, R>, options?: RunOptions | undefined) => Promise<Exit.Exit<A, E>>R>, options: RunOptions | undefinedoptions?: RunOptions | undefined) => interface Promise<T>Represents the completion of an asynchronous operation
Promise<import ExitExit.type Exit<A, E = never> = Exit.Success<A, E> | Exit.Failure<A, E>Represents the result of an Effect computation.
When to use
Use when you need to synchronously inspect whether an Effect computation
succeeded or failed.
Details
An Exit<A, E> is either Success<A, E> containing a value of type A, or
Failure<A, E> containing a Cause<E> describing why the computation
failed.
Since Exit is also an Effect, you can yield it inside Effect.gen.
Example (Pattern matching on an Exit)
import { Exit } from "effect"
const success: Exit.Exit<number> = Exit.succeed(42)
const failure: Exit.Exit<number, string> = Exit.fail("error")
const result = Exit.match(success, {
onSuccess: (value) => `Got value: ${value}`,
onFailure: (cause) => `Got error: ${cause}`
})
Namespace containing helper types shared by Exit values.
When to use
Use to reference helper types that describe the shared structure of Exit
values.
Exit<function (type parameter) A in <A, E>(effect: Effect<A, E, R>, options?: RunOptions | undefined): Promise<Exit.Exit<A, E>>A, function (type parameter) E in <A, E>(effect: Effect<A, E, R>, options?: RunOptions | undefined): Promise<Exit.Exit<A, E>>E>> =
import internalinternal.const runPromiseExitWith: <R>(
context: Context.Context<R>
) => <A, E>(
effect: Effect.Effect<A, E, R>,
options?: Effect.RunOptions | undefined
) => Promise<Exit.Exit<A, E>>