Node.js和Chrome中的不同行为

Question

In Node.js (ver. 0.12.0 ) I have a class with method defined like this:

In ./constructor.js :

function Pow() {}
Pow.prototype.wow = require("./wow/definition.js");

module.exports = Pow;

In ./wow/definition.js :

var Pow = require("../constructor.js");

function wow() {

  return new Pow();
}

module.exports = wow;

In ./index.js :

var Pow = require("./constructor.js");
var pow = new Pow();
pow.wow();

The last line of ./index.js throws the following error:

object is not a function
    at Pow.wow(./wow/definition.js:5:10)

Running the same code in Google Chrome (ver. 45.0.2454.101 64-bit ), which also uses the V8 engine but not the CommonJS require system, does not result in an error:

 function Pow() {} Pow.prototype.wow = wow; function wow() { return new Pow(); } var pow = new Pow(); pow.wow(); 

Can anyone tell me why, in Nodejs, require("./constructor.js") returns a constructor in ./index.js but a non-constructable object in ./wow/definition.js ?

Answer 1

As @slebetman mentions in his comment on the original question, support for circular dependencies in CommonJS, the specification most similar to the implementation of require() in NodeJs, is still somewhat buggy . So, avoid ciricular dependencies until support for them in NodeJs has been worked out.