[whatwg] Questions on error handling in web workers

Ian Hickson ian at hixie.ch
Wed Jul 15 17:17:22 PDT 2009

On Wed, 15 Jul 2009, Jian Li wrote:
> I have a couple questions regarding error handling in HTML 5 workers. In 
> the spec, it says "Whenever a runtime script error occurs in one of the 
> worker's scripts, if the error did not occur while handling a previous 
> script error, the user agent must report the error using the 
> WorkerGlobalScope object's onerror attribute.". Does it mean that 
> onerror attribute of WorkerContext would be called? In addition to the 
> errors being thrown?

The term "report the error" is defined here:


> The spec also says "For dedicated workers, if the error is still not 
> handled afterwards, or if the error occurred while handling a previous 
> script error, the user agent must queue a task to fire a worker error 
> event at the Worker object associated with the worker.".  What does it 
> mean by "the error is still not handled afterwards"? Does it mean that 
> the onerror attribute is not set for WorkerContext?

The term "not handled" is defined here:


Ian Hickson               U+1047E                )\._.,--....,'``.    fL
http://ln.hixie.ch/       U+263A                /,   _.. \   _\  ;`._ ,.
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