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diff --git a/node_modules/rxjs/src/internal/operators/map.ts b/node_modules/rxjs/src/internal/operators/map.ts
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+import { OperatorFunction } from '../types';
+import { operate } from '../util/lift';
+import { createOperatorSubscriber } from './OperatorSubscriber';
+
+export function map<T, R>(project: (value: T, index: number) => R): OperatorFunction<T, R>;
+/** @deprecated Use a closure instead of a `thisArg`. Signatures accepting a `thisArg` will be removed in v8. */
+export function map<T, R, A>(project: (this: A, value: T, index: number) => R, thisArg: A): OperatorFunction<T, R>;
+
+/**
+ * Applies a given `project` function to each value emitted by the source
+ * Observable, and emits the resulting values as an Observable.
+ *
+ * <span class="informal">Like [Array.prototype.map()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/map),
+ * it passes each source value through a transformation function to get
+ * corresponding output values.</span>
+ *
+ * ![](map.png)
+ *
+ * Similar to the well known `Array.prototype.map` function, this operator
+ * applies a projection to each value and emits that projection in the output
+ * Observable.
+ *
+ * ## Example
+ *
+ * Map every click to the `clientX` position of that click
+ *
+ * ```ts
+ * import { fromEvent, map } from 'rxjs';
+ *
+ * const clicks = fromEvent<PointerEvent>(document, 'click');
+ * const positions = clicks.pipe(map(ev => ev.clientX));
+ *
+ * positions.subscribe(x => console.log(x));
+ * ```
+ *
+ * @see {@link mapTo}
+ * @see {@link pluck}
+ *
+ * @param project The function to apply to each `value` emitted by the source
+ * Observable. The `index` parameter is the number `i` for the i-th emission
+ * that has happened since the subscription, starting from the number `0`.
+ * @param thisArg An optional argument to define what `this` is in the
+ * `project` function.
+ * @return A function that returns an Observable that emits the values from the
+ * source Observable transformed by the given `project` function.
+ */
+export function map<T, R>(project: (value: T, index: number) => R, thisArg?: any): OperatorFunction<T, R> {
+  return operate((source, subscriber) => {
+    // The index of the value from the source. Used with projection.
+    let index = 0;
+    // Subscribe to the source, all errors and completions are sent along
+    // to the consumer.
+    source.subscribe(
+      createOperatorSubscriber(subscriber, (value: T) => {
+        // Call the projection function with the appropriate this context,
+        // and send the resulting value to the consumer.
+        subscriber.next(project.call(thisArg, value, index++));
+      })
+    );
+  });
+}