Number methods (5..days etc) in JS

gistfile1.txt

// Stolen from https://github.com/mikemaccana/agave/blob/master/index.js
const MILLISECONDS_IN_SECOND = 1000,
  SECONDS_IN_MINUTE = 60,
  MINUTES_IN_HOUR = 60,
  HOURS_IN_DAY = 24,
  DAYS_IN_WEEK = 7,
  DAYS_IN_MONTH = 30,
  DAYS_IN_YEAR = 365

// Normally you'd name functions with a verb, but since 
// these are properties of Number, it's OK 
var seconds = function () {
  return this * MILLISECONDS_IN_SECOND
}

var minutes = function () {
  return this.seconds * SECONDS_IN_MINUTE
}

var hours = function () {
  return this.minutes * MINUTES_IN_HOUR
}

var days = function () {
  return this.hours * HOURS_IN_DAY
}

var weeks = function () {
  return this.days * DAYS_IN_WEEK
}

var years = function () {
  return this.days * DAYS_IN_YEAR
}

var newAttributes = {
  Number: {
    seconds,
    minutes,
    hours,
    days,
    weeks,
    years,
    // And the singular properties
    second: seconds,
    minute: minutes,
    hour: hours,
    day: days,
    week: weeks,
    year: years
  }
}

// Add sttribute as a non-enumerable property on obj with the name methodName
var addNewAttribute = function (objectName, methodName, method) {
  var objectToExtend = global[objectName]
  // Don't add if the method already exists
  if (!objectToExtend.prototype.hasOwnProperty(methodName)) {
    Object.defineProperty(objectToExtend.prototype, methodName, {
      get: method
    })
  }
}

for (var objectToGetNewAttribute in newAttributes) {
  for (var attributeName in newAttributes[objectToGetNewAttribute]) {
    addNewAttribute(objectToGetNewAttribute, attributeName, newAttributes[objectToGetNewAttribute][attributeName])
  }
}