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1/**
2 * This function takes one parameter and just returns it. Simply put,
3 * this is like `<T>(x: T): T => x`.
4 *
5 * ## Examples
6 *
7 * This is useful in some cases when using things like `mergeMap`
8 *
9 * ```ts
10 * import { interval, take, map, range, mergeMap, identity } from 'rxjs';
11 *
12 * const source$ = interval(1000).pipe(take(5));
13 *
14 * const result$ = source$.pipe(
15 * map(i => range(i)),
16 * mergeMap(identity) // same as mergeMap(x => x)
17 * );
18 *
19 * result$.subscribe({
20 * next: console.log
21 * });
22 * ```
23 *
24 * Or when you want to selectively apply an operator
25 *
26 * ```ts
27 * import { interval, take, identity } from 'rxjs';
28 *
29 * const shouldLimit = () => Math.random() < 0.5;
30 *
31 * const source$ = interval(1000);
32 *
33 * const result$ = source$.pipe(shouldLimit() ? take(5) : identity);
34 *
35 * result$.subscribe({
36 * next: console.log
37 * });
38 * ```
39 *
40 * @param x Any value that is returned by this function
41 * @returns The value passed as the first parameter to this function
42 */
43export declare function identity<T>(x: T): T;
44//# sourceMappingURL=identity.d.ts.map
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