SIGX203 · defineFactory returned a primitive#

Dev message

[sigx] defineFactory setup must return an object or function, got number.

Suggestion

Return the service object (or callable) from the factory setup — primitives cannot carry the dispose contract factories rely on.

What happened#

A defineFactory setup returned a primitive — a number, string, boolean, null or undefined.

Factories manage a lifecycle, not just a value: a scoped factory instance is created on first use and disposed when its scope ends. SignalX tracks that by hanging a dispose contract off the returned value, which only works for objects and functions. A primitive has nowhere to put it, so there'd be no way to ever clean the instance up.

Fix it#

Return the service itself:

TypeScript 
import { defineFactory } from 'sigx';

const useCounter = defineFactory(() => {
    const count = signal(0);

    return {
        get value() { return count.value; },
        increment() { count.value++; },
    };
}, 'scoped');

If what you want really is a single primitive, wrap it in an object so it has an identity to hang the lifecycle on:

TypeScript 
const useRequestId = defineFactory(() => ({ id: crypto.randomUUID() }), 'scoped');

A callable works too, when the service is naturally one function:

TypeScript 
const useTrack = defineFactory(() => {
    const queue: Event[] = [];
    return (e: Event) => queue.push(e);
}, 'scoped');

For a plain constant with no lifecycle, you don't need a factory at all — a module export or a defineInjectable is simpler.