Hi Joern, looks like the node was creaed in a bad import. I was sure that mkgmap drops all tags where the value is empty but this doesn't happen. The attached patch changes this. Anyway, it is probably also possible to create an empty tag in the style rules, so I think we have to decide if ele=* should match when ele has an empty tag value. Gerd ________________________________________ Von: mkgmap-dev <mkgmap-dev-bounces@lists.mkgmap.org.uk> im Auftrag von J J <joern.de@gmail.com> Gesendet: Donnerstag, 9. April 2020 23:21 An: Development list for mkgmap Betreff: [mkgmap-dev] handling of a key without a value https://www.openstreetmap.org/node/7278416985 That node seems to crash my style while trying to execute the following command: ele=* {echo 'ele=${ele}'; set ele_m='${ele|conv:"ft=>m"}'; echo 'ele_m=${ele}'; } The echo command produces "ele=" in the transcript, afterwards "java.lang.StringIndexOutOfBoundsException: String index out of range: -1" etc. The node contains any empty values. "ele" is the only of them my style uses. Observed in: mkgmap-r4478