simply-effect

better than all the rest 🎶

Simple wrapper around Effect.gen that allows writing generator functions in a cleaner way.

With plain effect:

import { Effect } from "effect";

export const getTodoById = (id: string) =>
  Effect.gen(function* () {
    const todo = yield* TodoService.getTodoById("some-id");
    if (todo.description.length < 2) {
      return yield* new ValidationError("Too small description");
    }
    return todo;
  });

Using simply-effect:

import { effect } from "simply-effect";

export const getTodoById = effect(function* (id: string) {
  const todo = yield* TodoService.getTodoById("some-id");
  if (todo.description.length < 2) {
    return yield* new ValidationError("Too small description");
  }
  return todo;
});

If the generator function has no arguments, then effect will work exactly the same as Effect.gen.

const value: Effect.Effect<void> = effect(function* () {
  yield* Console.log(1);
});

It can work together with classes as well, but an extra type annotations for this is needed:

class MyService {
  readonly local = 1;
  compute = effect(this, function* (this: MyService, add: number) {
    yield* Console.log(this.local + add);
  });
}