If you only describe half the problem, (less--how do you distinguish an "echo" from the "real thing"?), you only get half a solution. That said, the architecture stays the same.

You either filter events before you queue them, or after you dequeue them, whichever is more convenient and timely.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
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In reply to Re^3: How to wait for events, and not lose any, while processing them ? by BrowserUk
in thread How to wait for events, and not lose any, while processing them ? by Eyck

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