Effect.tryPromise

import { Effect } from 'effect';

//     ┌─── Effect.Effect<Response, never, never>
//     ▼
const fail = Effect.promise(() => fetch("not-a-url"));

fail
  .pipe(
    //               ┌─── never
    //               ▼
    Effect.catchAll((e) => Effect.succeed(console.error("handled inside:", e))),
    Effect.runPromise,
  )
  .then((x) => console.log("program ran to completion with", x))
  .catch((e) =>
    console.error("the error leaked outside our Effect boundary!", e),
  );

//     ┌─── Effect.Effect<Response, UnknownException, never>
//     ▼
const fail = Effect.tryPromise(() => fetch("not-a-url"));
// was: const fail = Effect.promise(() => fetch("not-a-url"));

// remainder unchanged
fail
    .pipe(
        //               ┌─── UnknownException
        //               ▼
        Effect.catchAll((e) =>
            Effect.succeed(console.error("handled inside:", e)),
        ),
        Effect.runPromise,
    )
    .then((x) => console.log("program ran to completion with", x))
    .catch((e) =>
        console.error("the error leaked outside our Effect boundary!", e),
    );

class FetchFailure extends Error {
  _kind = "FetchFailure" as const;
}

//     ┌─── Effect.Effect<Response, FetchFailure, never>
//     ▼
const fail = Effect.tryPromise({
    try: async () => fetch("not-a-url"),
    catch: (e) => new FetchFailure(`failed to fetch because ${e}`),
});

// code unchanged, but the error type has changed
fail
    .pipe(
        //               ┌─── FetchFailure
        //               ▼
        Effect.catchAll((e) =>
            Effect.succeed(console.error("handled inside:", e)),
        ),
        Effect.runPromise,
    )
    .then((x) => console.log("program ran to completion with", x))
    .catch((e) =>
        console.error("the error leaked outside our Effect boundary!", e),
    );

class RequestFailure extends Error {
  _kind = "RequestFailure" as const;
}

class ResponseFailure extends Error {
  _kind = "ResponseFailure" as const;
}

const get = (url: string) =>
  Effect.tryPromise({
    try: () => fetch(url),
    catch: (e) => new RequestFailure(`unable to get ${url} because ${e}`),
  }).pipe(
    Effect.flatMap((response) =>
      Effect.tryPromise({
        try: (): Promise<unknown> => response.json(),
        catch: () => new ResponseFailure(response.statusText),
      }),
    ),
  );

const success = get("https://httpbin.org/uuid").pipe(
  Effect.map((json) => console.log(json)),
  Effect.catchAll((e) => Effect.succeed(console.error(e))),
);

const badResponse = get("https://httpbin.org/status/418").pipe(
  Effect.map((json) => console.log(json)),
  Effect.catchAll((e) => Effect.succeed(console.error(e))),
);

const badRequest = get("no-way").pipe(
  Effect.map((json) => console.log(json)),
  Effect.catchAll((e) => Effect.succeed(console.error(e))),
);

const main = async () => {
  console.log("=== running 1 ===");
  await Effect.runPromise(success);
  console.log("=== running 2 ===");
  await Effect.runPromise(badResponse);
  console.log("=== running 3 ===");
  await Effect.runPromise(badRequest);
  console.log("=== done ===");
};

main();