import { createSelector, lruMemoize } from 'reselect' export interface RootState { todos: { id: number; completed: boolean }[] alerts: { id: number; read: boolean; type: string }[] } const selectAlertsByType = createSelector( [ (state: RootState) => state.alerts, (state: RootState, type: string) => type ], (alerts, type) => alerts.filter(todo => todo.type === type), { argsMemoize: lruMemoize, argsMemoizeOptions: { // This will check the arguments passed to the output selector. equalityCheck: (a, b) => { if (a !== b) { console.log('Changed argument:', a, 'to', b) } return a === b } } } )