Node.js File Module

module.js

a.js 

var b = require('./b')

b.b; // undefined

exports.a = 1;






b.js

var a = require('./a') -> a's module.exports

a.a; // 1

exports.b = 2;



$ node b

require(id) -> search file by id 
  -> file not found -> error
  -> file found -> 
    -> module.exports loaded -> return module.exports;
    -> not -> empty module.exports -> pass module.exports into file -> set flag loaded=true, run file