Keywords

There are not many keywords in Scrall by design. Consequently, you have a lot of freedom when it comes to naming things, but not total freedom. Avoid using the following keywords in names:

ITS // relative to nonlocal instance in reflexive hop
ME // for sending signals to self
AND, OR, NOT // in comparison/selection predicates
TRUE, FALSE // for convenience

Keywords are all in uppercase so that you can get away with a name like this:

dogs and cats ..= dogs + cats

The LHS is a labeled instance flow (assuming dogs, cats are also labeled instance flows)

But you can't do this!

dogs AND cats ..= dogs + cats // ERROR!

This won't work since you now have a boolean expression on the LHS.