Edge case: infinite loop/out of memory in certain situations

[Alexnortung]

In some scenarios computeds can get stuck in an infinite loop and/or cause out of memory.

Here is a minimal program that will get stuck:

import { computed, signal } from "alien-signals";

const fieldA = signal(false);
const fieldB = signal(false);

const a = computed(() => {
  return b() !== true ? fieldA() : null;
});

const b = computed((): boolean | null => {
  return a() !== true ? fieldB() : null;
});

console.log("a", a()); // false
console.log("b", b()); // false

fieldA(true);
console.log("Field A changed");

// BREAKS HERE when trying to get a
console.log("a", a());
console.log("b", b());

What I would expect:

At least that it would not get stuck in an infinite loop.
But I am not sure about the result.

---

I am not sure if this should be part of the core of alien-signals as the result may be a bit ambigous.

[volynetstyle]

This is the other side of the performance trade-off, not really an edge case.

The runtime assumes computed dependencies form a DAG and does not perform cycle detection in the hot path. As a result, cyclic computed graphs are unsupported and may not terminate. Ideally this should be reported in development mode, while production treats it as an invariant.