Testing functions for JS types -- more @ https://github.com/thekarel/jstypes

types.js

exports.isString = function(v) {
  return (typeof v === 'string');
}

exports.isInteger = function(v) {
  return (parseInt(v) === v)
}

exports.isFloat = function(v) {
  return ((v % 1) > 0)
}

exports.isBoolean = function(v) {
  return (typeof v === 'boolean')
}

exports.isNull = function(v) {
  return (v === null)
}

exports.isUndefined = function(v) {
  return (typeof v === 'undefined')
}

exports.isNan = function(v) {
  return (isNaN(v) && typeof v === 'number')
}

exports.isArray = function(v) {
  return (v !== null && typeof v === 'object' && typeof v.length === 'number')
}

exports.isObject = function(v) {
  return (v !== null && typeof v === 'object' && v.length === undefined)
}

exports.isFunction = function(v) {
  return (typeof v === 'function')
}