It isn't documented yet... but this is according to the current implementation.
I get why you might want to have this, as it greatly improves readability.
However it will also add quite a lot of memory usage to ESP8266.
Right now, you could use dummy tasks and through [taskname#taskvaluename] kind of syntax use this.
Only you need to use taskvalueset here.
You can however use taskname etc. as arguments for taskvalueset.
See:
https://espeasy.readthedocs.io/en/lates ... skvalueset
There are plans for "virtual tasks" which are about inbetween of dummy tasks and variables, but that's not yet implemented.
Mainly because this concept is not yet clear in my head how it should be used.
P.S.
When using taskvalueset, you might need to prefix any calculation with '=' when using it as an argument.
e.g. taskvalueset,foo,bar,=123+456
Or temporary store it in a var using 'let' and then copy it to the dummy task using taskvalueset.