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Edge case: infinite loop/out of memory in certain situations #123
Description
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.
Activity
volynetstyle commentedon Jun 10, 2026
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.