[whatwg] Web Workers API

[Oliver Hunt]

All meesaging through postMessage uses the internal structured cloning algorithm detailed at http://www.w3.org/TR/2010/WD-html5-20100304/Overview.html#internal-structured-cloning-algorithm

It's basically a deep copy, but has a few restrictions on the types cloned, and doesn't copy functions or the prototype property, etc.

--Oliver

On Jul 1, 2010, at 9:06 PM, Evan Ireland wrote:

> Hi,
> 
> The IDL for Worker in the Web Workers API specification shows:
> 
>    void postMessage(in any message, in optional MessagePortArray ports);
> 
> I have a question regarding the 'any' type for message.
> 
> If a caller of postMessage passes an object to a worker that is not a
> string, is it converted to a string or can non-string objects be propagated
> through to the onmessage(event) in the worker.
> 
> So if I write:
> 
> var w = new MyWorker('MyWorker.js');
> w.postMessage(new MyObject());
> 
> --------------
> // MyWorker.js
> 
> onmessage = function(event)
> {
>    var d = event.data;
>    // what type is 'd'?
> }
> 
> If 'd' is not a string, then is it a MyObject, and if so, how is it supposed
> to be marshalled by the inter-worker(thread) communication?
> 
> I suggest that whatever the answer, that this be covered when the spec
> document is next updated.
> 
> Thanks.
> 
>