Re: Synchronous postMessage for Workers?

On Thu, Nov 17, 2011 at 3:47 PM, Joshua Bell <jsbell@chromium.org> wrote:

> ^^^ Nit: That would revert back to being postMessage(), no new API on the
> Worker side.
>

Right, I just copied your example.  (You mean "no new API for sending
messages"--the "get the next event" method would be new API for workers.)

One concern with this overall approach is that any pending message would be
> grabbed, not just one intended as a response.
>

You just create separate MessagePorts to segregate different types of
messages.  messagePort.getMessageIfExists would only retrieve messages on
messagePort.

"Retrieve the first message from a list of message ports", akin to
poll/select, may also be useful, eg. getFirstMessage([port1, port2],
timeout).  I'm not sure if there are use cases for this, but it's worth
mentioning.

I agree that "return" makes more sense than "dispatch", since we're
> introducing this to support a linear programming style. On the other hand,
> you could emulate "return" with "dispatch" via helper functions that swap
> in a temporary onmessage handler (a variant on your
> getPendingMessageWithoutDelivery example in the older thread)
>

Right, you can emulate either using the other.  Alternatively, do both:
fire the event synchronously, then return it.

-- 
Glenn Maynard