[PATCH] Add method to get unique values in mapcss

[taylor.smock]

Lets say you want to compare ref tags from a way to ref tags in the parent relations.

If the way has ref=A9, int_ref=A9, and the parent relation has ref=A9, then a simple comparison will not work.

Example code:

  relation[type=route][route=road][ref] > way[ref][!regexp_test(concat("^(", join_list("|", uniq_list(split(";", join(";", tag_regex("ref")))), "|;?)+$"), join_list(";", uniq_list(sort_list(parent_tags("ref")))), "i")] {
    throwError: tr("Parent ref not in child ref");
  }

Notes on the sample mapcss code: It does not check to make certain that all parent refs are relevant to standard ref tagging schemes on ways (e.g., if the way is part of a tram route with a ref, it will trigger, even though most of the time tram route refs are not on the highway).

[taylor.smock]

New functions uniq and uniq_list along with a simple test to make certain they work.

[Don-vip]

In 15323/josm:

fix #18085 - Add method to get unique values in mapcss (patch by taylor.smock)

[Klumbumbus]

Please add docu at wiki:Help/Styles/MapCSSImplementation.

[taylor.smock]

Replying to Klumbumbus:

Please add docu at wiki:Help/Styles/MapCSSImplementation.

I've added it, along with tag_regex.