[PEAK] Trellis: tasks and discrete sensors

Phillip J. Eby pje at telecommunity.com
Thu Oct 9 13:21:06 EDT 2008

At 08:03 PM 10/9/2008 +0300, Sergey Schetinin wrote:
>This test shows that @task rules never get to see discrete values. It
>prints 'waiting' twice, so they are triggered, but sensor value is
>None both times.

This is a documented limitation, or at least it should be documented.  :)

Tasks can't read discrete values because a task step cannot be 
"undone".  This is why they are only run from the system event 
loop.  If you need to communicate discrete events to a task, you will 
need to write them to a list or something of that sort, and then have 
the task read and remove them.

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