// The chunk is requested, when you require the bundle
var waitForChunk = require("bundle-loader!./file.js");

// To wait until the chunk is available (and get the exports)
//  you need to async wait for it.
waitForChunk(function(file) {
    // use file like is was required with
    // var file = require("./file.js");
});
// wraps the require in a require.ensure block

var load = require("bundle-loader?lazy!./file.js");

// The chunk is not requested until you call the load function
load(function(file) {

});

require("bundle-loader?lazy&name=my-chunk!./file.js");