Why can I not use the "Signal parameter" virtual signal here?

[ZzZombo]

https://i.redd.it/21tbj8pln11e1.png

As you can see there is only the "Item parameter" signal. Because of this my generic train schedule idea doesn't work correctly. With the latter it doesn't resolve to anything and thus the train is stuck.

[ZzZombo]

How can I get the developers to comment on this matter? This makes my otherwise elegant train setup broken, and it seems to be a weird omission unless there is a technical reason for it.

[Tertius]

It seems the interrupt wildcards are hardcoded to the categories available in the waiting conditions. In a waiting condition that checks for cargo, you're only allowed to use the cargo wildcard, and in a waiting condition that checks for circuit signals, you're only allowed to use the signal wildcard. But not vice versa.

Seems a bug or at least an omission, since wildcard expansion takes place at interrupt processing at the source station, not at waiting condition processing at the destination station. It's not required to limit the wildcard usage this way.

It would be perfectly valid to match a signal wildcard at interrupt processing, then use the item you got in a cargo waiting condition in the schedule. This would enable the station to send a signal via circuit that shapes any waiting conditions created by interrupts in many ways.

In my opinion, create a feature request. May be implementation is as easy as relaxing the input filter slightly and offer all wildcards, no matter the condition type.

[ZzZombo]

I tested putting the "Signal" placeholder from the pipette tool and it doesn't get replaced by the game. I'm half torn if this is a bug and should be reported as such or an unimplemented feature.