Is Util Object

util.is.js

// Utils

  var is = {
    arr: function(a) { return Array.isArray(a) },
    obj: function(a) { return Object.prototype.toString.call(a).indexOf('Object') > -1 },
    svg: function(a) { return a instanceof SVGElement },
    dom: function(a) { return a.nodeType || is.svg(a) },
    num: function(a) { return !isNaN(parseInt(a)) },
    str: function(a) { return typeof a === 'string' },
    fnc: function(a) { return typeof a === 'function' },
    und: function(a) { return typeof a === 'undefined' },
    nul: function(a) { return typeof a === 'null' },
    hex: function(a) { return /(^#[0-9A-F]{6}$)|(^#[0-9A-F]{3}$)/i.test(a) },
    rgb: function(a) { return /^rgb/.test(a) },
    hsl: function(a) { return /^hsl/.test(a) },
    col: function(a) { return (is.hex(a) || is.rgb(a) || is.hsl(a)) }
  }