import { ObservableInput, from, Observable } from "rxjs"
import { SUSPENSE } from "@react-rxjs/core"
import { defaultStart } from "./internal-utils"

/**
 * A RxJS creation operator that prepends a SUSPENSE on the source observable.
 *
 * @param source$ Source observable
 */
export const suspend: <T>(
  source$: ObservableInput<T>,
) => Observable<T | typeof SUSPENSE> = <T>(source$: ObservableInput<T>) =>
  defaultStart(SUSPENSE)(from(source$)) as any