entries.ts

type A = { a: 1; b: 2 };
type ObjectToArray<O> = {
  [Key in keyof O]: [Key, O[Key]];
}[keyof O][];
type B = ObjectToArray<A>;

const entries = <O>(o: O): ObjectToArray<O> => {
  const a: ObjectToArray<O> = [];
  for (const key in o) {
    const element = o[key];

    a.push([key, element]);
  }

  return a;
};
const a: A = {
  a: 1,
  b: 2,
}
const b = entries(a);
type C = typeof b
type D = C[number]
type E = D[0]
type F = D[1]