[RFC] createInjectionToken with support of multi: true

[wanoo21]

I started to rewrite some of my libraries and added ngxtension.

I'm using createInjectionToken quite often and I've noticed I can't create a multi-token - multi: true.

I checked the source code and I don't see to be a way to mark it as multiple.

Maybe there's a workaround I can't find out?

[nartc]

That's right. I'll take a look at this.

[nartc]

@wanoo21 added a fix but I'd like to point this out.

https://github.com/nartc/ngxtension-platform/pull/98/files#diff-28c9dd83d9c535288ff51d6470317daabbcffec42e587608c98810c47c71cddcR111

You can see here that provideFn() is called twice in the providers array. The first call is to make sure the provided factory is run. If not, then the value returned will only include the 2nd call provideFn(2).

[wanoo21]

Cool, thank you, nice addition!
I'd like to provide some other suggestions.

How about adding support for the Generic type and marking the factory as optional?

So basically this:
export const TOKEN = new InjectionToken<MyType>();

becomes:
export const [injectFn, provideFn] = createInjectionToken<MyType>();

There's a problem though, I can't make it multi without providing the factory 🤷🏻‍♂️

Also, considering the code above, would this work?
provideFn(() => { const foo = inject(FOO); if (foo) return 'something' return 'something else' })

Instead of a simple value, to provide a factory!

This is how I manage it now:

[nartc]

@wanoo21 open a new issue on that please