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diff --git a/node_modules/rxjs/src/internal/operators/find.ts b/node_modules/rxjs/src/internal/operators/find.ts
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+import { Observable } from '../Observable';
+import { Subscriber } from '../Subscriber';
+import { OperatorFunction, TruthyTypesOf } from '../types';
+import { operate } from '../util/lift';
+import { createOperatorSubscriber } from './OperatorSubscriber';
+
+export function find<T>(predicate: BooleanConstructor): OperatorFunction<T, TruthyTypesOf<T>>;
+/** @deprecated Use a closure instead of a `thisArg`. Signatures accepting a `thisArg` will be removed in v8. */
+export function find<T, S extends T, A>(
+  predicate: (this: A, value: T, index: number, source: Observable<T>) => value is S,
+  thisArg: A
+): OperatorFunction<T, S | undefined>;
+export function find<T, S extends T>(
+  predicate: (value: T, index: number, source: Observable<T>) => value is S
+): OperatorFunction<T, S | undefined>;
+/** @deprecated Use a closure instead of a `thisArg`. Signatures accepting a `thisArg` will be removed in v8. */
+export function find<T, A>(
+  predicate: (this: A, value: T, index: number, source: Observable<T>) => boolean,
+  thisArg: A
+): OperatorFunction<T, T | undefined>;
+export function find<T>(predicate: (value: T, index: number, source: Observable<T>) => boolean): OperatorFunction<T, T | undefined>;
+/**
+ * Emits only the first value emitted by the source Observable that meets some
+ * condition.
+ *
+ * <span class="informal">Finds the first value that passes some test and emits
+ * that.</span>
+ *
+ * ![](find.png)
+ *
+ * `find` searches for the first item in the source Observable that matches the
+ * specified condition embodied by the `predicate`, and returns the first
+ * occurrence in the source. Unlike {@link first}, the `predicate` is required
+ * in `find`, and does not emit an error if a valid value is not found
+ * (emits `undefined` instead).
+ *
+ * ## Example
+ *
+ * Find and emit the first click that happens on a DIV element
+ *
+ * ```ts
+ * import { fromEvent, find } from 'rxjs';
+ *
+ * const div = document.createElement('div');
+ * div.style.cssText = 'width: 200px; height: 200px; background: #09c;';
+ * document.body.appendChild(div);
+ *
+ * const clicks = fromEvent(document, 'click');
+ * const result = clicks.pipe(find(ev => (<HTMLElement>ev.target).tagName === 'DIV'));
+ * result.subscribe(x => console.log(x));
+ * ```
+ *
+ * @see {@link filter}
+ * @see {@link first}
+ * @see {@link findIndex}
+ * @see {@link take}
+ *
+ * @param predicate A function called with each item to test for condition matching.
+ * @param thisArg An optional argument to determine the value of `this` in the
+ * `predicate` function.
+ * @return A function that returns an Observable that emits the first item that
+ * matches the condition.
+ */
+export function find<T>(
+  predicate: (value: T, index: number, source: Observable<T>) => boolean,
+  thisArg?: any
+): OperatorFunction<T, T | undefined> {
+  return operate(createFind(predicate, thisArg, 'value'));
+}
+
+export function createFind<T>(
+  predicate: (value: T, index: number, source: Observable<T>) => boolean,
+  thisArg: any,
+  emit: 'value' | 'index'
+) {
+  const findIndex = emit === 'index';
+  return (source: Observable<T>, subscriber: Subscriber<any>) => {
+    let index = 0;
+    source.subscribe(
+      createOperatorSubscriber(
+        subscriber,
+        (value) => {
+          const i = index++;
+          if (predicate.call(thisArg, value, i, source)) {
+            subscriber.next(findIndex ? i : value);
+            subscriber.complete();
+          }
+        },
+        () => {
+          subscriber.next(findIndex ? -1 : undefined);
+          subscriber.complete();
+        }
+      )
+    );
+  };
+}