8-2-index-types_avoid-types-polution.ts

type Phone = {
  id: string;
  features: {
    isWaterproof: boolean;
    ramAmount: number;
    cpu: string;
  };
  promotedFeature: keyof Phone['features'];
};

declare const phone: Phone;
phone.promotedFeature = 'cpu';

// how about create types with "features checks" based on this

const lazyChecks = {
  cpu: () => 'cool one',
  isWaterproof: () => 'skskskskdsajkdh',
  ramAmount: () => 'maaaaany',
};

type FeaturesChecks = {
  [K in keyof Phone['features']]: () => Phone['features'][K];
};

const featuresChecks: FeaturesChecks = {
  cpu: () => 'fast',
  isWaterproof: () => true,
  ramAmount: () => 8,
};

export {};