error NotFound { id: string }

service Users {
  find(id: string): User!NotFound
}

function greet(id: string) {
  return `Welcome, ${Users.find(id).name}`
    catch (e) => `No user ${e.id}`
}

export function main() {
  provide UsersLive {
    const [ada, missing] = await.all [greet("42"), greet("7")]
    Console.log(ada, missing)
  }
}

import { Data, Effect, Schedule } from "effect"

class FetchError extends Data.TaggedError("FetchError")<{
  readonly cause: unknown
}> {}

const getUser = (id: string) =>
  Effect.tryPromise({
    try: (signal) => fetch(`/users/${id}`, { signal }),
    catch: (cause) => new FetchError({ cause })
  })

// Typed failure, retried with backoff, bounded in time.
const program = getUser("42").pipe(
  Effect.retry({
    times: 3,
    schedule: Schedule.exponential("100 millis")
  }),
  Effect.timeout("5 seconds")
)