It can be done fully client side, but all javascript file names must be specified. For example, as array items:
function loadScripts(){
var directory = 'script/';
var extension = '.js';
var files = ['model', 'view', 'controller'];
for (var file of files){
var path = directory + file + extension;
var script = document.createElement("script");
script.src = path;
document.body.appendChild(script);
}
}