mapValues.ts

export function mapValues<A, B>(
  obj: { [key: string]: A },
  f: (x: A) => B
): { [key: string]: B } {
  const rv: { [key: string]: B } = {}
  for (const key in obj) {
    if (obj.hasOwnProperty(key)) {
      rv[key] = f(obj[key])
    }
  }
  return rv
}