es5 cyclic dependency add.js

es5-add.js

const subtractModule = require('./subtract.js');

exports.countAdd = 0;

exports.add = function(n = 0) {
  exports.countAdd++;
  console.log('countAdd', exports.countAdd);

  subtractModule.countSubtract++
  console.log('countSubtract from add file', subtractModule.countSubtract);

  if (n < 20) return subtractModule.subtractfn(n + 1);
}

subtractModule.subtractfn(exports.countAdd);