I was testing circular dependency with commonjs.
//index.js
console.log('main starting');
const a = require('./a.js');
const b = require('./b.js');
console.log('in main, a.done = %j, b.done = %j', a.done, b.done);
//a.js
console.log('a starting');
exports.done = false;
const b = require('./b.js');
console.log('in a, b.done = %j', b.done);
exports.done = true;
console.log('a done');
//b.js
console.log('b starting');
exports.done = false;
const a = require('./a.js');
console.log('in b, a.done = %j', a.done);
exports.done = true;
console.log('b done');
The result was
// output
main starting
a starting
b starting
in b, a.done = false
b done
in a, b.done = true
a done
in main, a.done = true, b.done = true
So index import a and a import b
b try to import a but a is not finished so a return unfinished module.
OK fine, I understood.
But what about esmodule syntax ?
I reproduced code like this.
//index.js
console.log('main starting');
import a from './a.js';
import b from './b.js';
console.log('in main, a.done = %j, b.done = %j', a.done, b.done);
//a.js
console.log('a starting');
export let done = false;
import {done as B_done} from './b.js';
console.log('in a, b.done = %j', B_done);
done = true;
console.log('a done');
export default {
done
}
//b.js
console.log('b starting');
export let done = false;
import {done as A_done} from './a.js';
console.log('in b, a.done = %j', A_done);
done = true;
console.log('b done');
export default {
done
}
But the result was changed.
ReferenceError: Cannot access 'A_done' before initialization
This error occrued.
Why is it giving me a different result than commonjs ?
Doesn't esmodule return unfinished modules?
You can actually find this code sample in here
