Listening to changes in a C++ variable from python

[lamthierry at gmail.com]

Is there some python method which can do the polling you are talking
about? Or can you send me a link to some existing example?

> It is not possible to "listen" to something that is not "emitting"
change
> notifications. Your variable "val" isn't "talking".
>
> Some languages let you listen to every variable, but that is because
> behind the scenes it is emitting every variable change as an event.
>
> In C++, in keeping with its general philosophy, it is not going to be
> possible to listen to an "int". You must either poll it, or wrap that
int
> in something that *will* emit change messages in some fashion that
> satisfies you. Given the circumstance of updating a progress bar, I'd
poll
> it about every quarter to half second.
>
> The correct answer changes depending on what you are doing with the
info
> and the level of control you exert over the source C++.