Enhance API compatibility: toJSON, toString

[dy]

Hi @WebReflection!

This adds toString and toJSON methods to make it more compatible with preact-signals API.

Lmk if you'd prefer casting result to string instead of {T}.

[WebReflection]

I've always been a bit skeptical about toJSON because an effect that re-produces JSON feels like a bit of a stretch ... do you have any obvious use case I am overlooking here?

[dy]

Preact-signals have it added in preactjs/signals#320 due to 2 reports.
Not having toJSON makes it harder serializing structures that allow signals, eg. deep-signals.
I don't remember if that is a blocker, but it would require unnecessary glue code.
All other signals implementations support that.

[dy]

An another compatibility issue here.
It seems effect ignores teardown function.

It would need wrapping effect like:

import {effect as _effect} from 'alien-signals'

export const effect = fn => {
  let teardown, dispose = _effect(() => (typeof teardown === 'function' && teardown(), teardown = fn()));
  return () => (typeof teardown === 'function' && teardown(), dispose());
}

[WebReflection]

but in practice you send JSON to servers and automatically sending new requests feels a bit weird to me ... anyway, mind amending the MR with your latest finding too? thanks!

[dy]

Sure, added with test.

[dy]

@WebReflection please merge if makes sense