I want to show bridges on my map but would like to remove their names so that when you mouseover them, it shows A5/Bridge rather than A5/A5 (assuming the road's ref is A5). However, if I try the following rule: highway=* & bridge=yes { delete 'name'; delete 'ref'; } [0x010107 continue resolution 24] I get an assertion: java.lang.AssertionError at uk.me.parabola.mkgmap.reader.osm.Tags.put(Tags.java:102) at uk.me.parabola.mkgmap.reader.osm.Tags.addExtraItems(Tags.java:299) at uk.me.parabola.mkgmap.reader.osm.Tags.access$300(Tags.java:41) at uk.me.parabola.mkgmap.reader.osm.Tags$1.hasNext(Tags.java:223) at uk.me.parabola.mkgmap.osmstyle.RuleSet.resolveType(RuleSet.java:72) at uk.me.parabola.mkgmap.osmstyle.StyledConverter.convertWay(StyledConverter.java:281) ... Is this a sensible way to remove the names? If not, what is? If the rule is good, why is it blowing up? Cheers, Mark