sagarpanchal/map-utils.ts

## map-utils.ts
export function mapListByProp<T extends object, K extends keyof T>(list: T[], key: K) {
  const output = new Map<T[K], T[]>()

  for (const item of list) {
    if (!(key in item)) continue
    const existingList = (output.has(item[key]) && output.get(item[key])) || []
    const updatedList = [...existingList, item]
    output.set(item[key], updatedList)
  }

  return output
}

export function mapToObject<K extends PropertyKey, V>(map: Map<K, V>) {
  const mapKeys = map.keys()
  const output = {} as Record<K, V>

  for (const key of mapKeys) {
    output[key] = map.get(key) as V
  }

  return output
}
	export function mapListByProp<T extends object, K extends keyof T>(list: T[], key: K) {
	const output = new Map<T[K], T[]>()

	for (const item of list) {
	if (!(key in item)) continue
	const existingList = (output.has(item[key]) && output.get(item[key])) \|\| []
	const updatedList = [...existingList, item]
	output.set(item[key], updatedList)
	}

	return output
	}

	export function mapToObject<K extends PropertyKey, V>(map: Map<K, V>) {
	const mapKeys = map.keys()
	const output = {} as Record<K, V>

	for (const key of mapKeys) {
	output[key] = map.get(key) as V
	}

	return output
	}