after.js

// a.js

"use strict";
var __es6_module__ = {}, __imports__ = [];

module.exports = {
  __es6_module__: __es6_module__
};

__imports__['./b'] = require('./b');
__imports__['./b'] = __imports__['./b'].__es6_module__ || __imports__['./b'];


__es6_module__["default"] = function even(n) {
  return n === 0 || __imports__['./b'].default(n - 1);
}

// b.js

"use strict";
var __es6_module__ = {}, __imports__ = [];

module.exports = {
  __es6_module__: __es6_module__
};

__imports__['./a'] = require('./a');
__imports__['./a'] = __imports__['./a'].__es6_module__ || __imports__['./a'];


__es6_module__["default"] = function odd(n) {
  return n === 0 || __imports__['./a'].default(n - 1);
}

before.js

// a.js

import odd from './b';

export default function even(n) {
  return n === 0 || odd(n - 1);
}

// b.js

import even from './a';

export default function odd(n) {
  return n === 0 || even(n - 1);
}