diff --git a/npm/ng-packs/packages/core/src/lib/services/track-by.service.ts b/npm/ng-packs/packages/core/src/lib/services/track-by.service.ts index 9576a287f2..aa72942ec0 100644 --- a/npm/ng-packs/packages/core/src/lib/services/track-by.service.ts +++ b/npm/ng-packs/packages/core/src/lib/services/track-by.service.ts @@ -1,15 +1,17 @@ import { Injectable, TrackByFunction } from '@angular/core'; import { O } from 'ts-toolbelt'; +export const trackBy = (key: keyof T): TrackByFunction => (_, item) => item[key]; + +export const trackByDeep = ( + ...keys: T extends object ? O.Paths : never +): TrackByFunction => (_, item) => keys.reduce((acc, key) => acc[key], item); + @Injectable({ providedIn: 'root', }) export class TrackByService { - by(key: keyof T): TrackByFunction { - return (_, item) => item[key]; - } + by = trackBy; - byDeep(...keys: T extends object ? O.Paths : never): TrackByFunction { - return (_, item) => keys.reduce((acc, key) => acc[key], item); - } + byDeep = trackByDeep; }