javascript - can you call a function while loading data in D3 js -

i trying figure out if there way can call function while loading data in d3.js. code below, not sure if on right track, seems simple cant work

d3.json("country_data.json", mac.call(country_data));   function mac(e) {  //i  function perform operations. //the data in file country_data passed function } 

if had ideas on how can implement appreciate it, thanks.

your code passing result of calling mac() should passing reference mac so...

d3.json("country_data.json", mac);  function mac(error, countrydata) {   if (error) {     // deal error   } else {     // perform operations on countrydata   } } 

or declare callback anonymous function inline call d3.json:

d3.json("country_data.json", function (error, countrydata) {   if (error) {     // deal error   } else {     // perform operations on countrydata   } });