Binary Based Enum Read Sum

bingen.ts

function bingen(size) {
  let c;
  return Array.from({length: size}, (y, k) => c = (c||1) * 2);
}

example.ts

enum SuperTypes {
  SUBSCRIBER = 2,
  SPEAKER = 4,
  MODERATOR = 8,
  ADMIN = 16,
  MASTER = 32,
}

const given = SuperTypes.SUBSCRIBER + SuperTypes.MODERATOR + SuperTypes.ADMIN + SuperTypes.MASTER;

const result = read(SuperTypes, given);

console.log(result);

/**
 * Reads a given binary based Enum and a number then
 * retrieves each enum that is part of the number
 * @param _enum
 * @param sum
 * @returns []
 */
function read(_enum, sum: number) {

  let next;
  const found = [];

  while ( sum > 0 )
  {
    next = findClosest(getEnumValues(_enum), sum);
    sum = sum % next;
    found.push(next);
  }

  return found.map(v => _enum[v]);

  function findClosest(arr, x) {
    return arr.reduce(function(prev, curr) {
      return ( (Math.abs(curr - x) < Math.abs(prev - x) ) && curr <= x ? curr : prev);
    });
  }

  function getEnumValues(__enum) {
    return Object.keys(__enum)
      .filter(k => typeof __enum[k as any] !== "number")
      .map(num => parseInt(num));
  }

}