blob: 460413d62bc831754dc397760051e93e72b8956f [file] [log] [blame]
import { MonoTypeOperatorFunction } from '../types';
/**
* The Max operator operates on an Observable that emits numbers (or items that can be compared with a provided function),
* and when source Observable completes it emits a single item: the item with the largest value.
*
* ![](max.png)
*
* ## Examples
* Get the maximal value of a series of numbers
* ```ts
* import { of } from 'rxjs';
* import { max } from 'rxjs/operators';
*
* of(5, 4, 7, 2, 8).pipe(
* max(),
* )
* .subscribe(x => console.log(x)); // -> 8
* ```
*
* Use a comparer function to get the maximal item
* ```typescript
* import { of } from 'rxjs';
* import { max } from 'rxjs/operators';
*
* interface Person {
* age: number,
* name: string
* }
* of<Person>(
* {age: 7, name: 'Foo'},
* {age: 5, name: 'Bar'},
* {age: 9, name: 'Beer'},
* ).pipe(
* max<Person>((a: Person, b: Person) => a.age < b.age ? -1 : 1),
* )
* .subscribe((x: Person) => console.log(x.name)); // -> 'Beer'
* ```
*
* @see {@link min}
*
* @param {Function} [comparer] - Optional comparer function that it will use instead of its default to compare the
* value of two items.
* @return {Observable} An Observable that emits item with the largest value.
* @method max
* @owner Observable
*/
export declare function max<T>(comparer?: (x: T, y: T) => number): MonoTypeOperatorFunction<T>;