generic typesafe state projector - proxy usecase

fromState.ts

// Instead of selector helpers like `export const getHasError = (state: AppUIState) => state.hasError;`
// use this. The typing is compatible with ngrx and gives you type hinting also (just dont forget to provide generic!)

const fromState = <T = {[key: string]: any}>() => {
  return (new Proxy({}, {
    get: (target: {}, p: string | number | symbol) => (state) => state[p]
  })) as {[key in keyof T]: (state: T) => T[key]};
};