IE-compatible data attribute getter/setter

get_set_data_attribute.js

Object.prototype.data = function (prop, val) {
  var _return,
  		notIE = ( this.dataset !== undefined );
                
  return ( notIE )? // not IE
  						( typeof val === "undefined" ) ? // get data value
              	this.dataset[prop] : this.dataset[prop] = val
            : // is IE
            	( typeof val === "undefined" ) ? // get data value
              	this.getAttribute('data-' + prop) : this.setAttribute('data-' + prop, val);
};