Simple shim for the Dataset API

dataset-api-shim.js

// Shim for the Dataset API to set and get data
var data = (function() {
   var supported = 'dataset' in document.createElement('div');
   return function(element, property, value) {
      if (arguments.length === 2) {
         return supported ? element.dataset[property] : element.getAttribute('data-' + property);
      } else if (arguments.length === 3) {
         return supported ? element.dataset[property] = value : element.setAttribute('data-' + property, value);
      }
   };
})();

// Shim for the Dataset API to remove data
var removeData = (function() {
   var supported = 'dataset' in document.createElement('div');
   return function(element, property) {
      return supported ? delete element.dataset[property] : element.removeAttribute('data-' + property);
   };
})();