What would happen if these files were run using CommonJS?
// file1.js - CommonJS
const value = require('./file2');
console.log(value);
// file2.js
const value = require('./file1');
console.log(value);
In this CommonJS circular dependency scenario: 1) When file1.js requires file2.js, the execution of file1.js is paused, 2) file2.js begins execution and tries to require file1.js, 3) Since file1.js is already being loaded but not finished, Node.js returns a partial copy of its exports (empty object at this point), 4) file2.js completes with this partial export, 5) Control returns to file1.js with file2's exports, 6) This behavior can lead to unexpected undefined values if not carefully managed, 7) This is why circular dependencies in CommonJS need careful consideration of execution order and export timing.