feat(core): add injectNonNullish$

this returns an Observable<boolean> based on the source Signal

Author: nartc

libs/core/src/index.ts

@@ -16,6 +16,7 @@ export * from './lib/utils/attach';
 export * from './lib/utils/before-render';
 export * from './lib/utils/is';
 export * from './lib/utils/make';
+export * from './lib/utils/non-nullish';
 export * from './lib/utils/object-events';
 export * from './lib/utils/parameters';
 export * from './lib/utils/resolve-ref';

libs/core/src/lib/utils/non-nullish.ts

@@ -0,0 +1,8 @@
+import { Injector, Signal } from '@angular/core';
+import { toObservable } from '@angular/core/rxjs-interop';
+import { assertInjector } from 'ngxtension/assert-injector';
+import { map } from 'rxjs';
+
+export function injectNonNullish$(sig: Signal<unknown>, { injector }: { injector?: Injector } = {}) {
+	return assertInjector(injectNonNullish$, injector, () => toObservable(sig).pipe(map((val) => val != null)));
+}