Add notes about ensure/debounceEvent not supporting async events

[julienma]

Checklist

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• [ ] I have added tests that prove my fix is effective or that my feature works.
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What was done

Add a note in the docs that we don't currently support async events, cf. https://github.com/rangle/redux-beacon/issues/286#issuecomment-423023024.

Associated Issues

• #286

:heart: Thanks

Thanks for taking the time to help out with the project, it's much appreciated :slightly_smiling_face:

[ttmarek]

Thanks so much for this!

The additions to the ensure doc are perfect. But, debounceEvent actually should work with async events. If possible, could you remove those changes and just leave the additions to the ensure docs?

[julienma]

Oh, sure.

But, what you mean is that I should be able to do this?

const emitEvent1 = debounceEvent(60*1000, emitEvent1Validated);
const emitEvent1Validated = ensure(validator,
  logEvent((action) => ({
    type: 'My Event'
  }))
);

I'm pretty sure I tried both debounceEvent(100, ensure(...)) and ensure(validator, debounceEvent(...)), and couldn't make it work any way.

I'm waiting for your confirmation before rolling back https://github.com/rangle/redux-beacon/pull/288/commits/e3dbf6421f14c5685bed89ce40e58be2d3819e15.

[ttmarek]

Hmm...odd. That snippet should work. ensure will always return a plain old synchronous event definition. And the debounceEvent util should work with any plain old synchronous event definition as seen in the type definitions:

function debounceEvent(
  msDelay: number,
  eventDef: EventDefinition
): EventDefinition {
 ...
}