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- import { Operator } from '../Operator';
- import { Subscriber } from '../Subscriber';
- import { OperatorFunction } from '../types';
- /**
- * 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
- * ```javascript
- * const clicks = fromEvent(document, 'click');
- * const positions = clicks.pipe(map(ev => ev.clientX));
- * positions.subscribe(x => console.log(x));
- * ```
- *
- * @see {@link mapTo}
- * @see {@link pluck}
- *
- * @param {function(value: T, index: number): R} 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 {any} [thisArg] An optional argument to define what `this` is in the
- * `project` function.
- * @return {Observable<R>} An Observable that emits the values from the source
- * Observable transformed by the given `project` function.
- * @method map
- * @owner Observable
- */
- export declare function map<T, R>(project: (value: T, index: number) => R, thisArg?: any): OperatorFunction<T, R>;
- export declare class MapOperator<T, R> implements Operator<T, R> {
- private project;
- private thisArg;
- constructor(project: (value: T, index: number) => R, thisArg: any);
- call(subscriber: Subscriber<R>, source: any): any;
- }
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