[whatwg] Asynchronous database API feedback

Thomas Broyer t.broyer at gmail.com
Wed Dec 12 06:12:39 PST 2007

2007/12/11, Krzysztof Żelechowski:
> Allowing the script to wait until the transaction completes would be
> enough to provide synchronization, wouldn't it?  A stubborn programmer
> can still do it: make a transaction set an event upon completion and
> make the script loop until that event is set.  Upon the theory that the
> transaction in question is a quickie, it would be quite acceptable,
> especially if the script engine fiddled with thread priorities a bit.
> If I am right, it is not such a big issue after all.

It'd only work in a multi-thread environment; otherwise, script might
be executed synchronously in response to user-input triggered events.
For example, I played a bit with PalmOS programming a few years ago
(before they release the Tungsten series). At that time (might have
changed since then), there were only two threads: one to receive and
queue user-input events and the other where your code was running
(with an "event loop" to consume pending events). In these conditions,
simulating a synchronous API with an asynchronous one (might happen:
send data over the network and having an event back for the response)
and a loop don't work, your loop has to be your event loop, where you
would queue back every event that's not telling you your asynchronous
call has "returned".

Thomas Broyer

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