initial commit: scaffolding

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diff --git a/node_modules/rxjs/src/internal/observable/race.ts b/node_modules/rxjs/src/internal/observable/race.ts
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+import { Observable } from '../Observable';
+import { innerFrom } from './innerFrom';
+import { Subscription } from '../Subscription';
+import { ObservableInput, ObservableInputTuple } from '../types';
+import { argsOrArgArray } from '../util/argsOrArgArray';
+import { createOperatorSubscriber } from '../operators/OperatorSubscriber';
+import { Subscriber } from '../Subscriber';
+
+export function race<T extends readonly unknown[]>(inputs: [...ObservableInputTuple<T>]): Observable<T[number]>;
+export function race<T extends readonly unknown[]>(...inputs: [...ObservableInputTuple<T>]): Observable<T[number]>;
+
+/**
+ * Returns an observable that mirrors the first source observable to emit an item.
+ *
+ * ![](race.png)
+ *
+ * `race` returns an observable, that when subscribed to, subscribes to all source observables immediately.
+ * As soon as one of the source observables emits a value, the result unsubscribes from the other sources.
+ * The resulting observable will forward all notifications, including error and completion, from the "winning"
+ * source observable.
+ *
+ * If one of the used source observable throws an errors before a first notification
+ * the race operator will also throw an error, no matter if another source observable
+ * could potentially win the race.
+ *
+ * `race` can be useful for selecting the response from the fastest network connection for
+ * HTTP or WebSockets. `race` can also be useful for switching observable context based on user
+ * input.
+ *
+ * ## Example
+ *
+ * Subscribes to the observable that was the first to start emitting.
+ *
+ * ```ts
+ * import { interval, map, race } from 'rxjs';
+ *
+ * const obs1 = interval(7000).pipe(map(() => 'slow one'));
+ * const obs2 = interval(3000).pipe(map(() => 'fast one'));
+ * const obs3 = interval(5000).pipe(map(() => 'medium one'));
+ *
+ * race(obs1, obs2, obs3)
+ *   .subscribe(winner => console.log(winner));
+ *
+ * // Outputs
+ * // a series of 'fast one'
+ * ```
+ *
+ * @param sources Used to race for which `ObservableInput` emits first.
+ * @return An Observable that mirrors the output of the first Observable to emit an item.
+ */
+export function race<T>(...sources: (ObservableInput<T> | ObservableInput<T>[])[]): Observable<any> {
+  sources = argsOrArgArray(sources);
+  // If only one source was passed, just return it. Otherwise return the race.
+  return sources.length === 1 ? innerFrom(sources[0] as ObservableInput<T>) : new Observable<T>(raceInit(sources as ObservableInput<T>[]));
+}
+
+/**
+ * An observable initializer function for both the static version and the
+ * operator version of race.
+ * @param sources The sources to race
+ */
+export function raceInit<T>(sources: ObservableInput<T>[]) {
+  return (subscriber: Subscriber<T>) => {
+    let subscriptions: Subscription[] = [];
+
+    // Subscribe to all of the sources. Note that we are checking `subscriptions` here
+    // Is is an array of all actively "racing" subscriptions, and it is `null` after the
+    // race has been won. So, if we have racer that synchronously "wins", this loop will
+    // stop before it subscribes to any more.
+    for (let i = 0; subscriptions && !subscriber.closed && i < sources.length; i++) {
+      subscriptions.push(
+        innerFrom(sources[i] as ObservableInput<T>).subscribe(
+          createOperatorSubscriber(subscriber, (value) => {
+            if (subscriptions) {
+              // We're still racing, but we won! So unsubscribe
+              // all other subscriptions that we have, except this one.
+              for (let s = 0; s < subscriptions.length; s++) {
+                s !== i && subscriptions[s].unsubscribe();
+              }
+              subscriptions = null!;
+            }
+            subscriber.next(value);
+          })
+        )
+      );
+    }
+  };
+}