主文件中的 JS 按需 require()

Question

Say I have a root.js which is requiring certain file, like:

var x = require('x.js');
var y = require('y.js');

function f_x() { return x.foo(); }
function f_y() { return y.foo(); }

f_y();  // This logic only needs y to get resolved

Thus in such a case, how can we load y only when f_y() occurs, ie, it is on-demand.
This is the solution for on-demand require in the required file ('x.js' or 'y.js'): On-demand require()
But since there is no exports in the root file, thus its getters can't be defined like that.

Answer 1

You can delay the require call until it's needed like this:

function f_x() {
  var x = require('./x.js');
  return x.foo();
}
function f_y() {
  var y = require('./y.js');
  return y.foo();
}

f_y();