| import { groupBy as higherOrder, GroupedObservable } from '../operators/groupBy'; |
| export { GroupedObservable }; |
| /* tslint:enable:max-line-length */ |
| /** |
| * Groups the items emitted by an Observable according to a specified criterion, |
| * and emits these grouped items as `GroupedObservables`, one |
| * {@link GroupedObservable} per group. |
| * |
| * <img src="./img/groupBy.png" width="100%"> |
| * |
| * @example <caption>Group objects by id and return as array</caption> |
| * Observable.of<Obj>({id: 1, name: 'aze1'}, |
| * {id: 2, name: 'sf2'}, |
| * {id: 2, name: 'dg2'}, |
| * {id: 1, name: 'erg1'}, |
| * {id: 1, name: 'df1'}, |
| * {id: 2, name: 'sfqfb2'}, |
| * {id: 3, name: 'qfs3'}, |
| * {id: 2, name: 'qsgqsfg2'} |
| * ) |
| * .groupBy(p => p.id) |
| * .flatMap( (group$) => group$.reduce((acc, cur) => [...acc, cur], [])) |
| * .subscribe(p => console.log(p)); |
| * |
| * // displays: |
| * // [ { id: 1, name: 'aze1' }, |
| * // { id: 1, name: 'erg1' }, |
| * // { id: 1, name: 'df1' } ] |
| * // |
| * // [ { id: 2, name: 'sf2' }, |
| * // { id: 2, name: 'dg2' }, |
| * // { id: 2, name: 'sfqfb2' }, |
| * // { id: 2, name: 'qsgqsfg2' } ] |
| * // |
| * // [ { id: 3, name: 'qfs3' } ] |
| * |
| * @example <caption>Pivot data on the id field</caption> |
| * Observable.of<Obj>({id: 1, name: 'aze1'}, |
| * {id: 2, name: 'sf2'}, |
| * {id: 2, name: 'dg2'}, |
| * {id: 1, name: 'erg1'}, |
| * {id: 1, name: 'df1'}, |
| * {id: 2, name: 'sfqfb2'}, |
| * {id: 3, name: 'qfs1'}, |
| * {id: 2, name: 'qsgqsfg2'} |
| * ) |
| * .groupBy(p => p.id, p => p.name) |
| * .flatMap( (group$) => group$.reduce((acc, cur) => [...acc, cur], ["" + group$.key])) |
| * .map(arr => ({'id': parseInt(arr[0]), 'values': arr.slice(1)})) |
| * .subscribe(p => console.log(p)); |
| * |
| * // displays: |
| * // { id: 1, values: [ 'aze1', 'erg1', 'df1' ] } |
| * // { id: 2, values: [ 'sf2', 'dg2', 'sfqfb2', 'qsgqsfg2' ] } |
| * // { id: 3, values: [ 'qfs1' ] } |
| * |
| * @param {function(value: T): K} keySelector A function that extracts the key |
| * for each item. |
| * @param {function(value: T): R} [elementSelector] A function that extracts the |
| * return element for each item. |
| * @param {function(grouped: GroupedObservable<K,R>): Observable<any>} [durationSelector] |
| * A function that returns an Observable to determine how long each group should |
| * exist. |
| * @return {Observable<GroupedObservable<K,R>>} An Observable that emits |
| * GroupedObservables, each of which corresponds to a unique key value and each |
| * of which emits those items from the source Observable that share that key |
| * value. |
| * @method groupBy |
| * @owner Observable |
| */ |
| export function groupBy(keySelector, elementSelector, durationSelector, subjectSelector) { |
| return higherOrder(keySelector, elementSelector, durationSelector, subjectSelector)(this); |
| } |
| //# sourceMappingURL=groupBy.js.map |
