Re: [Emc-developers] using the dummysig trick (was Re: pid with derivative inputs)

[Chris M. <chr...@ho...>]

________________________________
From: andy pugh <bod...@gm...>
Sent: June 14, 2018 12:44 PM
To: EMC developers
Subject: Re: [Emc-developers] using the dummysig trick (was Re: pid with derivative inputs)


I have no recollection of an API being added. So, before I go ahead
and use the dummysig trick in a component, did we reach consensus
about whether it is to be encouraged, deprecated or  abhorred?



My 2 cents:
I would not encourage the dummysig trick (meaning behavior is different based on whether a signal is connected or not)
This is black magic voodoo. - brilliant but -  unintuitive, hard to recognize the error, easy to create the error.
In fact pncconf connects signal names to components and doesn't necessarily connect them to anything.
When PID added this trick I was unaware - and pncconf created the error - Peter eventually noticed while diagnosing a user's
problem.
Wouldn't a pin created to set the behavior be safer?
In fact isn't that was what param's were made for? (not that I would use params for anything today, since you can't connect to them)

Chris M