[rules-dev] Free form expressions?

It appears that it ain't as free as it should be: Person( age > $age * 2 ) Unable to return Declaration for identifier '$age * 2' : [Rule name='exa1'] Person( isAdult() ) Unable to Analyse Expression isAdult(): [Error: no such identifier: isAdult] Book( "Jones" memberOf authors ) Unable to build constraint as '"Jones"' is invalid Cheers Wolfgang