how about changing the first line of your DSL map to... [condition][]{varname} is a Volume where {constraints} = {varname} : RawVolumeTs (where {constraints} ) That way, your DSL would read... rule "RT(2) against FT(32)" when V1 is a Volume where status is "NA" and sourceId is "ABC" V2 is a Volume where status is "NA" and sourceId is "XYZ" then end and the resulting DRL would read... rule "RT(2) against FT(32)" when V1 : RawVolumeTs (status == "NA", sourceId == "ABC") V2 : RawVolumeTs (status == "NA", sourceId == "XYZ") then End