1 d3.html = function(url, callback) {

     2   d3.text(url, "text/html", function(text) {

     3     if (text != null) { // Treat empty string as valid HTML.

     4       var range = document.createRange();

     5       range.selectNode(document.body);

     6       text = range.createContextualFragment(text);

     7     }

     8     callback(text);

     9   });

    10 };