Compiler ignores constants in head atoms of an inference rule

[alldefector]

This rule

@weight(f)
tag(w, "GROOVY") :- features(w, f).

is compiled as if it's

@weight(f)
tag(w, t) :- features(w, f).

[netj]

This is pretty nasty.. can the following be a workaround?

@weight(f)
tag(w, t) :- features(w, f), t = "GROOVY".

[alldefector]

Yes, that works.