There are some special codes that one can use to have zoom dependent length of labels in maps: "{2" - Non-spacing prefix indicator. "{3" - Prefix indicator. "{4" - Non-spacing suffix indicator. "{5" - Suffix indicator. So for example we have a road called B51 (from the ref field) and Streetname (from the name field). Ideally we could now write in the style-file: { set name='{3{$ref}{$name}' } however mkgmap does not correctly enact this and removes the leading"{" so instead of shortening the name, I end up with useless "2", "3", "4" and "5" inside the names. name: Brucker Ersatzstrasse ref: 335 rule: {name '{3${ref|highway-symbol:oval:6:4}{5${name}' | '${ref|highway-symbol:oval:6:4}' | '${name}'} i.e. instead of the following label being encoded like this: {3B335 {5BRUCKER ERSATZSTRASSE it ends up like this: 3~[0x2f]B335 5BRUCKER ERSATZSTRASSE