Changes between Initial Version and Version 1 of Ru:Help/Styles/MapCSSImplementation

Timestamp:

2018-03-30T09:01:12+02:00 (7 years ago)

Author:

ak099

Comment:

--

Ru:Help/Styles/MapCSSImplementation

@@ +1 @@
+[[TranslatedPages(revision=146,outdated=Страница в процессе перевода)]]
+[[PageOutline(1-10,Содержание)]]
+Эта страница документирует подробности реализации языка [osmwiki:MapCSS/0.2 MapCSS] в JOSM. Он используется в следующих элементах JOSM:
+
+* [wikitr:/Styles Стили отрисовки карты]
+* [wikitr:/Rules Правила валидатора]
+* [wikitr:/Help/Action/Search Диалог поиска]
+
+== Общая структура ==
+Таблица стилей MapCSS содержит правила в следующей форме:
+{{{
+#!mapcss
+selector {
+    prop: value;
+    /* ... */
+    prop: value;
+    /* and/or */
+    set: class;
+    set: .class;
+}
+}}}
+Алгоритм поиска стилей для заданного объекта таков:
+{{{
+ - для каждого правила:
+     если селектор применим к объекту, задать свойства из блока { }
+ - проанализировать последний список свойств и сгенерировать стили из него
+}}}
+
+MapCSS использует формат '''комментариев''' из CSS (`/* ... */`). Заметьте, что при комментировании больших частей файла MapCSS некоторые конструкции могут вызвать непредвиденный конец комментария, например:
+{{{
+#!mapcss
+/*
+*[highway][name =~ /^R(\.|:)? .*/] { /* группа символов в конце регулярного выражения приводит к непредвиденному завершению комментария */
+        throwWarning: tr("foo");
+}
+*/
+}}} 
+
+== Селекторы ==
+''Селекторы'' — это выражения для фильтрации правил MapCSS. Правило применяется к объекту карты, только если его селектор соответствует объекту.
+
+Селекторы в MapCSS отличаются от стандартных в CSS для WWW. MapCSS поддерживает лишь подмножество стандартных селекторов CSS, но в него добавлены дополнительные селекторы, требующиеся для данных OSM.
+
+Некоторые простые примеры:
+{{{
+#!mapcss
+/* применяется к линиям с тегом highway=residential */
+way[highway=residential] {  /*  the styles */}
+
+/* применяется к новым замкнутым линиям на слое 1, если они имеют тег amenity=parking и access=public, и если
+ * уровень масштаба в диапазоне от 11 до 14 
+ */
+way|z11-14[amenity=parking][access=public]:closed:new::layer_1 {...}
+
+
+area[amenity=parking][access=public], area[amenity=parking][!access] {...}
+relation[type=route][route=foot] > way::relation_underlay {..}
+}}}
+
+
+Другие элементы ('''type'''-, '''zoom'''- , '''condition''' selector, '''pseudo classes''', '''layer identifier''', '''grouping''' и '''child combinator''') поясняются ниже.
+
+
+=== Селектор Type ===
+
+{{{#!th align=left valign=top 
+'''Selector'''
+}}}
+{{{#!th align=left valign=top
+'''Description'''
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+*
+}}}
+{{{#!td align=left  valign=top    
+Matches with any object
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+{{{node}}}, {{{way}}}, {{{relation}}}
+}}}
+{{{#!td align=left  valign=top    
+Matches with the osm objects of the given type.
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+{{{area}}}
+}}}
+{{{#!td align=left  valign=top    
+Matches with any area regardless of whether the area border is only modelled with a single way or with a set of ways glued together with a relation.
+{{{
+#!mapcss
+area[natural=beach] {...} 
+/* ... is equal to ... */
+way[natural=beach], relation[type=multipolygon][natural=beach] {...} 
+}}}
+Note that {{{area}}} selects unclosed ways as well, so it may be useful to add the {{{:closed}}} pseudo class. The JOSM Validator will give a warning for unclosed ways that have an area style.
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+{{{meta}}}
+}}}
+{{{#!td align=left  valign=top    
+The {{{meta}}} selector starts a special rule that should stand at the beginning of the file. It gives some general information on the style sheet. All software that supports MapCSS should be able to parse this sections without errors, so do not use exotic syntax extensions in this part.
+{{{
+#!mapcss
+meta {
+    title: "Parking lanes";   /* title shown in the menu */
+    icon: "images/logo.png";  /* small icon shown in the menu next to the title */
+    version: "1.2";           /* the version of the style */
+    description: "...";       /* one or two sentences of describing the style */
+    author: "...";            /* the author(s) of the style */
+    link: "http://...";       /* URL to the web page of the style */
+    min-josm-version: 6789;   /* the minimum JOSM version where this style works */
+}
+}}}
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+{{{canvas}}}
+}}}
+{{{#!td align=left  valign=top    
+Some style information not specific to nodes, ways or relations.
+{{{
+#!mapcss
+canvas {
+    fill-color: #ffffea; /* the former background-color is deprecated since r7110 */
+    default-points: false;
+    default-lines: false;
+}
+}}}
+{{{#!th
+'''Key'''
+}}}
+{{{#!th
+'''Description'''
+}}}
+{{{#!th
+'''Value Format'''
+}}}
+{{{#!th
+'''Default Value'''
+}}}
+|-
+{{{#!td
+{{{fill-color}}}
+}}}
+{{{#!td
+Specifies the overall fill/background color (`background-color` is deprecated since r7110).
+}}}
+{{{#!td
+''Color''
+}}}
+{{{#!td align=center
+{{{black}}}
+}}}
+|-
+{{{#!td
+{{{default-points}}}
+}}}
+{{{#!td
+Whether default point style should be added to nodes where no style applies.
+}}}
+{{{#!td
+''Boolean''
+}}}
+{{{#!td align=center
+{{{true}}}
+}}}
+|-
+{{{#!td
+{{{default-lines}}}
+}}}
+{{{#!td
+Whether default line style should be added to ways where no style applies.
+}}}
+{{{#!td
+''Boolean''
+}}}
+{{{#!td align=center
+{{{true}}}
+}}}
+}}}
+
+=== Child selector ===
+If a node is part of a way, we say that it is a ''child'' of this way. Similarly, if a node, a way, or a relation is a member of a relation, we say, that it is a ''child'' of this relation.
+
+In MapCSS you can use a '''child selector''' which matches only if both the parent and the child object match.
+
+Example:
+{{{
+#!mapcss
+/*
+ * only matches for a way which is a child of a relation with tags 
+ * type=route and route=foot
+ */
+relation[type=route][route=foot] > way {...}
+}}}
+
+Notes:
+* Zoom selector and Layer identifier are only relevant for the part to the right of the > sign.
+* The functions ''prop()'' and ''is_prop_set()'' are only supported on the right side of the > sign.
+* The functions ''parent_tag'' and ''parent_tags'' (see below) can be used to access tags from the parent(s).
+* For compatibility with the MapCSS 0.2 standard, `relation[type=route][route=foot] way {/*...*/}`, without the greather-than-sign `>` is supported, too. However, no [[#Linkselector]] may be specified in this case.
+
+
+=== Parent selector ===
+In addition to child selectors, JOSM supports the notion of a '''parent selector'''. Note, that parent selectors are a JOSM-specific extension of MapCSS not present in other MapCSS implementations.
+
+Similar to a child selector, a parent selector only matches if both the parent and the child object match. In contrast to the child selector, the character < is used. 
+
+In contrast to the child selector, the parent object will be "selected". In other words, the properties in the {{{{...}}}}-Declaration Block apply to the object on the right hand side of the "<" sign.
+
+Example:
+{{{
+#!mapcss
+/*
+ * matches for a highway which has at least one node tagged as traffic_calming=*
+ */
+node[traffic_calming] < way[highway] {...}
+}}}
+
+=== Condition selector ===
+Selectors can include a set of conditions. If any of these conditions evaluates to false, the selector doesn't match and the style
+rule isn't applied.
+
+An '''attribute condition''' specifies a condition on a tag of an OSM object. 
+
+[=#condition_selector_operators]
+{{{#!th align=left valign=top 
+'''Operator'''
+}}}
+{{{#!th align=left valign=top
+'''Description'''
+}}}
+{{{#!th align=left valign=top
+'''Example'''
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+`=`
+}}}
+{{{#!td align=left  valign=top    
+Exact match of the value.
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+way[highway=residential]                   /* without quotes always case insensitive */
+node[name="My name"]                       /* use quotes for if value includes spaces or if case sensitive matching is important */
+node["MY_Special_TAG"="another value"]     /* use quotes for tag names if case sensitive matching is required */
+node["ÖPVN"=tram]                          /* use quotes for tag keys with special characters */
+                                           /*   note that these are not common in OSM at the moment */
+}}}
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+`!=`
+}}}
+{{{#!td align=left  valign=top    
+Value not equal 
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+way[highway!=residential]                   /* without quotes always case insensitive */
+node[name!="My name"]                       /* use quotes if value includes spaces or if case sensitive matching is important */
+node["MY_Special_TAG"!="another value"]     /* use quotes for tag names if case sensitive matching is required */
+node["name:fr"!="mon nome"]                 /* use quotes for tag names with special characters like colons*/
+}}}
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+`<`, `>`, `<=`, `>=`
+}}}
+{{{#!td align=left  valign=top    
+Comparision for numeric values.
+
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+node[population >= 50000]                   /* population greater than or equal to 50000 */
+node[ele = 3000]                            /* elevation with exactly 3000 meters */
+}}}
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+{{{^=}}}
+}}}
+{{{#!td align=left  valign=top    
+Prefix match
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+node[name ^= "myprefix"]                    /* value starts with 'myprefix' */
+}}}
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+`$=`
+}}}
+{{{#!td align=left  valign=top    
+Postfix match
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+node[name $= "mypostfix"]                   /* value ends with 'mypostfix' */
+}}}
+}}}
+|-----------------------------------------------
+{{{#!td align=left  valign=top
+`*=`
+}}}
+{{{#!td align=left  valign=top    
+Substring match
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+node[name *= "my substring"]                 /* value contains the substring 'my substring' */
+}}}
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+`~=`
+}}}
+{{{#!td align=left  valign=top    
+List membership
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+*[vending~=stamps]                          /* the tag value for the tag 'vending' consists of a list of ;-separated values    */
+                                            /* and one of these values is 'stamps'                                             */
+}}}
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+`=~`
+}}}
+{{{#!td align=left  valign=top    
+[https://download.oracle.com/javase/8/docs/api/java/util/regex/Pattern.html#sum Regular expression] match
+
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+*[name=~/^My_pattern.*/]                    /* the value of the tag 'name' matches with the regular expression '^My_pattern.*' */
+                                            /* Note, that reqular expressions have to be enclosed in /.../                     */                  
+}}}
+Case-insensitive matching can be enabled via the embedded flag expression `(?i)` (see [https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html#CASE_INSENSITIVE Pattern.CASE_INSENSITIVE]).
+{{{
+#!mapcss
+*[name =~ /^(?U)(\p{Lower})+$/]              /* name consists of only lower case unicode characters */                 
+}}}
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+`!~` (since r6455)
+}}}
+{{{#!td align=left  valign=top    
+negated [https://download.oracle.com/javase/8/docs/api/java/util/regex/Pattern.html#sum Regular expression] match
+
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+*[surface!~/paved|unpaved/]
+}}}
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+`∈` ([http://www.fileformat.info/info/unicode/char/2208/index.htm U+2208], since r6609)
+}}}
+{{{#!td align=left  valign=top    
+element of
+
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+node[amenity=parking] ∈ *[amenity=parking] {
+  throwWarning: tr("{0} inside {1}", "amenity=parking", "amenity=parking");
+}
+}}}
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+`⧉` ([http://www.fileformat.info/info/unicode/char/29c9/index.htm U+29C9], since r6613)
+}}}
+{{{#!td align=left  valign=top    
+crossing
+
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+area:closed:areaStyle ⧉ area:closed:areaStyle {
+  throwOther: tr("Overlapping Areas");
+}
+}}}
+takes `layer` tag into account if set (since r12986)
+}}}
+
+Since r6554, it is possible to prefix the "value" (i.e., expression after the operator) with a `*` in order to "de-reference" it (i.e., obtain consider it as another key and obtain its value). Thus, `[key1 = *key2]` or `[key1=*key2]` compares the value of `key1` with the value of `key2`, and `[key =~ */pattern/]` considers the value of the key `pattern` as a regular expression and matches it against the value of `key`.
+
+In addition, you can test whether a tag is present or not:
+
+{{{#!th align=left valign=top 
+'''Condition'''
+}}}
+{{{#!th align=left valign=top
+'''Example'''
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+Presence of tag
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+way[highway]                     /* matches any way with a tag 'highway'                                              */
+way["VALSOU"]                    /* use quotes if case sensitive matching is required                                 */
+way["name:fr"]                   /* use quotes if the tag name includes special caracters (white space, colons, etc.) */
+}}}
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+Absence of tag
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+way[!highway]                     /* matches any way which does not have a tag 'highway'                               */
+way[!"VALSOU"]                    /* use quotes if case sensitive matching is required                                 */
+way[!"name:fr"]                   /* use quotes if the tag name includes special caracters (white space, colons, etc.) */
+}}}
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+Presence of tag by [https://download.oracle.com/javase/8/docs/api/java/util/regex/Pattern.html#sum Regular expression] match (since r6547)
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+way[/^addr:/]                     /* matches any `addr:*` key */
+}}}
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+Absence of tag by Regular expression match
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+way[!/^addr:/]                    /* matches any way which does not have a tag 'addr:*' */
+}}}
+}}}
+
+You can test whether the value of a tag is logical truth value. The value is evaluated to true, if it is either 
+"yes", "true", or "1". All other values are evaluated to false.
+
+{{{#!th align=left valign=top 
+'''Condition'''
+}}}
+{{{#!th align=left valign=top
+'''Example'''
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+Testing for truth value
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+way[oneway?]                  /* matches any way with a truth value in the tag 'oneway'  */
+}}}
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+Testing for false value (since r6513)
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+way[oneway?!]                  /* matches any way with a false value in the tag 'oneway'  */
+}}}
+}}}
+
+=== Territory selector ===
+
+You can test whether an object is located inside or outside of a specific territory. JOSM has an internal database for this. The territories file is an osm file and can be downloaded [/export/HEAD/josm/trunk/data/boundaries.osm here] and opened in JOSM to investigate it [attachment:boundaries.png (screenshot preview)]. It contains borders of all countries of the world. Due to performance reasons the borders are simplified. They can be refined for special cases on request. The territories are "tagged" with their [https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2 ISO_3166-1_alpha-2 codes]. USA, Canada, China, India and Australia have additional boundaries for their subdivisions. See the following examples on how to use the territory selectors. Territory selectors are less useful in mappaint styles and can be very resource heavy there. However they are much more useful for [wiki:Help/Validator/MapCSSTagChecker mapcss based validator rules]. To select territories with left-hand-traffic or right-hand-traffic, there is a simpler way, see [#PseudoClasses]. See #10387 for main implementation of this feature.
+
+{{{
+#!mapcss
+node[inside("FR")]                    /* matches any node located inside of France (this includes all the overseas territories)                                     */
+node[inside("FX")]                    /* matches any node located inside of Metropolitan France (i.e. only the mainland part with its near islands including Corse) */
+node[inside("EU")]                    /* matches any node located inside of the European Union                                                                      */
+node[inside("FR,DE")]                 /* matches any node located inside of France __OR__ inside of Germany                                                         */
+node[inside("US-FL")]                 /* matches any node located inside of the US state Florida                                                                    */
+
+node[outside("FR")]                   /* matches any node located outside of France                                                                                 */
+node[outside("FR,DE")]                /* matches any node located outside of France __AND__ outside of Germany                                                      */
+node[inside("US")][outside("US-FL")]  /* matches any node located inside of the USA except the state Florida                                                        */
+}}}
+
+=== Link selector ===
+In a child selector, you can formulate conditions on the link between a parent and a child object. 
+
+If the parent is a relation, you can formulate conditions for the ''role'' a member objects has in this relation.
+{{{
+#!mapcss
+relation[type=route] >[role="link"] way {  /* matches any way which is a member of route relation with role 'link' */ 
+   color: blue;
+}
+}}}
+
+{{{#!th align=left valign=top 
+'''Operator'''
+}}}
+{{{#!th align=left valign=top
+'''Description'''
+}}}
+{{{#!th align=left valign=top
+'''Example'''
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+`=`
+}}}
+{{{#!td align=left  valign=top    
+Exact match of the role name. The name name {{{role}}} is compulsory in this context. 
+}}}
+{{{#!td align=left  valign=top    
+{{{
+#!mapcss
+relation >[role=residential] way           /* without quotes always case insensitive */
+relation >[role="My name"]   way           /* use quotes for if the role value includes spaces or if case sensitive matching is important */
+}}}
+}}}
+
+The operators {{{!=, ^=, $=, *=, and ~=}}} are supported too. Please refer to [#condition_selector_operators condition selector operators].
+
+Nodes in ways and members in relations are ordered. You can formulate conditions on the position of a node in a way or a member
+object in a relation. Positive numbers count from first to last element, negative numbers (since r8236) count from last to first element.
+
+{{{
+#!mapcss
+relation[type=route] >[index=1] way {  /* matches the first way which is a member of route relation  */ 
+   color: blue;
+}
+
+way >[index=-1] node {  /* matches the last node of a way  */ 
+   symbol-stroke-color: green;
+}
+
+way!:closed >[index=1] node!:connection,
+way!:closed >[index=-1] node!:connection {  /* matches all single way end nodes */ 
+   symbol-stroke-color: green;
+}
+}}}
+
+
+=== Zoom selector ===
+You can decorate a type selector with a '''zoom selector'''. The zoom selector restricts the range of zoom levels 
+at which the respective MapCSS rule is applied.
+
+{{{#!th align=left valign=top 
+'''Example'''
+}}}
+{{{#!th align=left valign=top
+'''Description'''
+}}}
+|-------------------------------------------------------------------------------
+|| {{{way|z12 {...} }}} || At zoom level 12 ||
+|| {{{way|z13-15 {...} }}} || From 13 to 15 ||
+|| {{{way|z16- {...} }}} || 16 and above ||
+|| {{{way|z-12 {...} }}} || 12 and below ||
+|| {{{way {...} }}} || any zoom level ||
+
+The precise definition of scale ranges for each zoom level may change in the future. By rule of thumb you can expect to be approximately at zoom level ''n'' when imagery displays slippymap tiles of level ''n''.
+
+
+=== Pseudo Classes ===
+See [/doc/org/openstreetmap/josm/gui/mappaint/mapcss/Condition.PseudoClasses.html Javadoc] for the up-to-date list of pseudo classes supported by JOSM's MapCSS implementation.
+
+|| {{{:closed}}} || true for ways where the first node is the same as the last and for any (completely downloaded) multipolygon relation ||
+|| {{{:closed2}}} || same as above, but this one ignores if a mulipolygon is downloaded completely (since r9099) ||
+|| {{{:completely_downloaded}}} || true for a relation whose members are all downloaded (since r9099) ||
+|| {{{:new}}} || all new objects ||
+|| {{{:connection}}} || true for nodes that are used by more than one way ||
+|| {{{:unconnected}}} || true for nodes that are not used by any way (since r6687) ||
+|| {{{:tagged}}} || What JOSM considers tagged, i.e. an object that with a tag key other than the following: {{{source*, source_ref, note, comment, converted_by, created_by, watch*, fixme, FIXME, description, attribution}}} (version r4008; in this list, {{{*}}} is a glob)
+|| {{{:righthandtraffic}}} || true if there is right-hand traffic at the current location (since r7193); see [[left-right-hand-traffic]] for screenshot of areas ||
+|| {{{:clockwise}}} || Whether the way is closed and oriented clockwise, or non-closed and the 1st, 2nd and last node are in clockwise order. ||
+|| {{{:anticlockwise}}} || Whether the way is closed and oriented anticlockwise, or non-closed and the 1st, 2nd and last node are in anticlockwise order. ||
+|| {{{:unclosed_multipolygon}}} || true for fully loaded unclosed multipolygon relations (since r8252) ||
+|| {{{:open_end}}} || to select end nodes of unclosed multipolygon relations with `relation:unclosed_multipolygon >:open_end node` (since r8252) ||
+|| {{{:in-downloaded-area}}} || true if an object is within source area and false if in the hatched area (since r8495). ||
+|| {{{:selected}}} || true if an object is selected in the editor (since r9341). ||
+|| {{{:modified}}} || changed objects (since r7193). ||
+You can also negate pseudo classes. E.g. {{{!:new}}} for all old objects.
+
+=== Layer Identifier ===
+
+Layers can be used to create more than one style for a single object. Here is an example:
+{{{
+#!mapcss
+way[highway=secondary] {
+    width: 3;
+    color: yellow;
+}
+
+way[highway=tertiary] {
+    width: 2;
+    color: orange;
+}
+
+way[access][access!=public]::non_public_access_layer {
+    width: +2; 
+    color:red; 
+    dashes: 2; 
+    object-z-index:-1.0;
+}
+
+way[bridge]::bridge_layer {
+    width: +3; 
+    color:#000080;
+    opacity:0.5;
+    object-z-index:1.0; 
+}
+}}}
+This draws all secondary and tertiary roads in yellow and orange respectively. Any road with an access tag other than public will get an extra line style below ('''{{{object-z-index:-1.0;}}}''') the main line. If that part of the street happens to be a bridge, it will also get a half transparent blue overlay. The relative width value ('''{{{width: +2;}}}''') refers to the width on the default layer (2 or 3 in this case).
+
+The name for the layer can be any identifier.
+
+If you omit the layer in the selector, this is the same as using {{{::default}}}. 
+
+One more example:
+{{{
+#!mapcss
+node[amenity=parking] {
+    icon-image: "presets/vehicle/parking/parking.svg";    /* displays the josm internal parking icon in the default layer */
+    text: ref;                                            /* displays the value of the key ref as text in the default layer */
+}
+
+node[amenity=parking][fee=yes]::fee {
+    icon-image: "presets/money/exchange.svg";             /* displays the josm internal exchange icon in the fee layer */
+    icon-offset-x: 14;                                    /* shift the icon */
+    icon-offset-y: -12;                                   /* shift the icon */
+    text: charge;                                         /* displays the value of the key charge as text in the fee layer */
+    text-offset-x: 16;                                    /* shift the text */
+    text-offset-y: 17;                                    /* shift the text */
+}
+}}}
+The result looks this way:
+
+[[Image(multiple_icons_and_texts.png)]]
+
+In addition, you can use the * layer to override and initialize all layers.[[br]]
+It overrides all existing subparts, so
+
+{{{
+#!mapcss
+way::A { a; } 
+way::B { b; } 
+way::* { c; } 
+}}}
+is equivalent to
+{{{
+#!mapcss
+way::A { a; } 
+way::B { b; } 
+way::A { c; } 
+way::B { c; }
+}}}
+And it initializes new subparts. In other words: 
+{{{
+#!mapcss
+way::* { a; } 
+way::A { b; } 
+}}}
+is equivalent to 
+{{{
+#!mapcss
+way::A {} 
+way::* { a; } 
+way::A { b; } 
+}}}
+which is in turn the same as 
+{{{
+#!mapcss
+way::A { a; } 
+way::A { b; } 
+}}}
+or
+{{{
+#!mapcss
+way::A { a; b; }
+}}}
+
+
+=== Grouping ===
+
+Rules with common declaration block can be grouped into one:
+{{{
+#!mapcss
+area[landuse=forest] { color: green;   width: 2; }
+area[natural=wood] { color: green;   width: 2; }
+}}}
+is the same as
+{{{
+#!mapcss
+area[landuse=forest], area[natural=wood] { color: green;   width: 2; }
+}}}
+
+=== Classes ===
+You may assign classes to matched elements, and define other selectors using those classes:
+
+{{{
+#!mapcss
+/* assigning classes */
+selector {
+  set class;
+  /* or equivalently */
+  set .class;
+}
+
+/* matching classes */
+way.class, node[foo=bar].class {
+  /* ... */
+}
+}}}
+
+
+Example for assigning/matching a class named `path`:
+{{{
+#!mapcss
+way[highway=footway] { set path; color: #FF6644; width: 2; }
+way[highway=path]    { set path; color: brown; width: 2; }
+way.path { text:auto; text-color: green; text-position: line; text-offset: 5; }
+}}}
+You can also negate classes. E.g. {{{way!.path}}} for all ways, which are not part of the class ''.path''.
+
+== @supports rule for conditional processing [''since 8087''] ==
+
+@supports rules are used to skip a section of the style under certain conditions. Typically you want to use a feature which is introduced in a newer version of JOSM, but like to have a fall back style for users of older JOSM clients. Example:
+{{{
+#!mapcss
+@supports (min-josm-version: 9789) {
+    way[highway] {
+        width: 4;
+        color: orange;
+    }
+    /* fancy new stuff */
+    /* ... */
+}
+
+@supports (max-josm-version: 9788) {
+    way[highway] {
+        width: 4;
+        color: blue;
+    }
+    /* fall back mode, using more simple features */
+    /* ... */
+}
+
+@supports (icon-offset-x) {
+    /* only if icon-offset-x property is supported */
+    node[amenity] {
+        icon-offset-x: 5;
+    }
+}
+}}}
+
+The syntax closely matches the official [https://drafts.csswg.org/css-conditional/ css syntax]. The following conditions are supported:
+
+{{{#!th
+'''Condition'''
+}}}
+{{{#!th
+'''Description'''
+}}}
+|-
+{{{#!td
+(''<mapcsskey>'')
+}}}
+{{{#!td
+Check if a certain mapcss key is supported, e.g. `repeat-image` or `icon-offset-x`.
+}}}
+|-
+{{{#!td
+(min-josm-version: ''<number>'')
+}}}
+{{{#!td
+Only include {{{@supports}}} section when the current version of JOSM is greater than or equal to the specified number.
+}}}
+|-
+{{{#!td
+(max-josm-version: ''<number>'')
+}}}
+{{{#!td
+Only include {{{@supports}}} section when the current version of JOSM is lower than or equal to the specified number.
+}}}
+|-
+{{{#!td
+(user-agent: ''<string>'')
+}}}
+{{{#!td
+Only include {{{@supports}}} section when the name of the editor / renderer matches the given string. In JOSM, the only accepted value is {{{josm}}}. 
+}}}
+
+Conditions can be combined with {{{and}}}:
+
+{{{
+#!mapcss
+@supports (min-josm-version: 8087) and (max-josm-version: 8200) {
+ /* only for JOSM versions 8087 to 8200 */
+}
+}}}
+
+Other logical operators like {{{or}}} and {{{not}}} can also be used. Parentheses are needed if you want to combine different logical operators:
+
+{{{
+#!mapcss
+@supports ((min-josm-version: 8087) and (max-josm-version: 8200)) or (user-agent: myEditor) {
+  /* for JOSM version 8087 to 8200 and for the editor called "myEditor" */
+}
+}}}
+
+Since @supports rules are only supported in JOSM 8087 and later, you should also specify this as minimum JOSM version in the meta selector:
+
+{{{
+#!mapcss
+meta {
+    min-josm-version: "8087"; /* This style uses @supports rules */
+    /* ... */
+}
+}}}
+
+== Style settings ==
+
+[[Help/Dialog/MapPaint/StyleSettings|Styles settings]] are used to provide the user settings to customize a mappaint style. The user can use them in the MapPaint dialog. Style settings are availible since r7450. The internal style provides style settings since r7454. Note that there are plans to extend the implementation of style settings (currently there are only boolean values supported), so the mapcss syntax for style settings could change in the future (see #10435).
+
+create a setting:
+{{{
+#!mapcss
+setting::highway_casing {
+  type: boolean;
+  label: tr("Draw highway casing");
+  default: true;
+}
+}}}
+use a setting:
+{{{
+#!mapcss
+way[highway][setting("highway_casing")] {
+  casing-width: 2;
+  casing-color: white;
+}
+}}}
+
+== Properties ==
+
+=== General properties ===
+
+||=  '''Key''' =||= '''Description''' =||= '''Value Format''' =||= '''Default Value''' =||
+|| {{{z-index}}}                                 || Specify the order the objects are drawn: The objects with higher z-index are drawn on top of objects with lower z-index || ''Number'' (can be negative) ||  0  ||
+|| {{{major-z-index}}} || Similar to {{{z-index}}}, but it has higher priority than {{{z-index}}}. So if one object has a higher {{{major-z-index}}} than the other, it is drawn on top. If the {{{major-z-index}}} is the same, {{{z-index}}} decides. || ''Number'' (can be negative) ||  Depends on style element: area: 1, casing: 2, left-/right-casing: 2.1, line-pattern: 2.9, line: 3, point: 4, default-point: 4.1, line-text: 4.9, point-text: 5   ||
+|| {{{object-z-index}}} || Similar to {{{z-index}}}, but has lower priority. Controls the painting order for overlapping objects. E.g. for two crossing ways with text: Use {{{z-index}}} or {{{major-z-index}}} if you first want to draw the two lines and then the two captions. Use {{{object-z-index}}} if one of the ways should be completely on top of the other. || ''Number'' (can be negative) ||  0  ||
+|| {{{modifier}}} || Better control, whether a default line / node symbol is generated by JOSM. This happens when there is no proper style ({{{modifier=false}}}) found on any layer. || {{{false}}} or {{{true}}} || {{{false}}} for the default layer and {{{true}}} for any other layer ||
+
+Note that due to performance reasons the values for the three z-indexes are limited to 24 bit float values with max. 5 decimal digits. Currently the internal mappaint style uses values with max. 2 digits before and after the decimal separator. To avoid problems use values of z-indexes between -99.999 and +99.999. (See also #14485)
+
+
+=== Icon and symbol styles ===
+
+||=  '''Key''' =||= '''Description''' =||= '''Value Format''' =||= '''Default Value''' =||
+|| {{{icon-image}}} || The icon at node position. See also [wiki:Help/Styles/Images Images]. || ''Image'' ||  -  ||
+|| {{{icon-opacity}}} || Opacity of the icon image || ''Opacity'' ||  1.0  ||
+|| {{{icon-width}}} || Width of the icon. If only one of the properties {{{icon-width}}} and {{{icon-height}}} is given, the image will be scaled proportionally. The icon will keep the original size, if neither {{{icon-width}}} nor {{{icon-height}}} is set. || ''Number'' ||  -  ||
+|| {{{icon-height}}} || Height of the icon. (See {{{icon-width}}}) || ''Number'' ||  -  ||
+|| `icon-offset-x` || Shift the icon in horizontal direction (positive values to the right) (since r8085) || ''Number'' ||  0  ||
+|| `icon-offset-y` || Shift the icon in vertical direction (positive values downwards) (since r8085) || ''Number'' ||  0  ||
+|| `icon-rotation` || Rotate the icon clockwise or anti clockwise (negative value)(since r8260) || `[rad]`, `[rad]rad`, `[deg]°`, `[deg]deg`, `[grad]grad`, `[turn]turn` ([https://developer.mozilla.org/en/docs/Web/CSS/angle definition]) or a cardinal direction (e.g. `northeast` or `sw`); See also the functions `degree_to_radians`, `cardinal_to_radians`. ||  -  ||
+|| `icon-position` || Define the position of the icon for areas. Same as `text-position` (since r11730). || {{{center}}}, {{{inside}}}, {{{line}}} || {{{center}}} ||
+|| {{{symbol-shape}}}                               || Display a symbol at the position of the node || {{{square}}}, {{{circle}}}, {{{triangle}}}, {{{pentagon}}}, {{{hexagon}}}, {{{heptagon}}}, {{{octagon}}}, {{{nonagon}}}, {{{decagon}}} ||  -  ||
+|| {{{symbol-size}}} || Size of the symbol || ''Number'', can be relative ("+4") ||  10  ||
+|| {{{symbol-stroke-width}}} || outline stroke width || ''Width'' ||  1.0 if {{{symbol-stroke-color}}} is set  ||
+|| {{{symbol-stroke-color}}} || line color || ''Color'' || {{{#FFC800}}} if {{{symbol-stroke-width}}} is set ||
+|| {{{symbol-stroke-opacity}}} || line opacity || ''Opacity'' ||  1.0  ||
+|| {{{symbol-fill-color}}} || fill color for the shape || ''Color'' || {{{blue}}}, unless either {{{symbol-stroke-width}}} or {{{symbol-stroke-color}}} is set ||
+|| {{{symbol-fill-opacity}}} || fill opacity || ''Opacity'' || 1.0  ||
+|| {{{text-...}}}, {{{font-...}}} ||||||  general text & font properties  ||
+|| {{{text-anchor-horizontal}}} || horizontal text label placement || {{{left}}}, {{{center}}}, {{{right}}} ||  {{{right}}}  ||
+|| {{{text-anchor-vertical}}} || vertical text label placement || {{{above}}}, {{{top}}}, {{{center}}}, {{{bottom}}}, {{{below}}} ||  {{{bottom}}}  ||
+
+Do not rely on the default values for {{{symbol-...}}} properties (except for {{{opacity}}}). They are intended for "quick & dirty" style sheets and should be set to an explicit value.
+
+
+
+
+
+=== Line styles ===
+||=  '''Key''' =||= '''Description''' =||= '''Value Format''' =||= '''Default Value''' =||
+|| {{{width}}} || Line width || ''Width'' ||  -  ||
+|| {{{color}}} || Line color || ''Color'' ||  value of {{{fill-color}}} or (if unset) JOSM's default untagged color ({{{#808080}}}) ||
+|| {{{opacity}}} || How transparent the line is. || ''Opacity'' ||  1.0  ||
+|| {{{dashes}}} || An array of alternating on/off lengths || list of numbers, e.g. [[br]]> 15, 5 [[br]][[br]]may be written as expression: [[br]] > {{{list(3, 4, 5, 6)}}} [[br]][[br]]or the keyword {{{none}}}[[br]]to turn dashes off ||  -  ||
+|| {{{dashes-offset}}} || shift the dash pattern by a certain amount || ''Number'' (>= 0) ||  0  ||
+|| {{{dashes-background-color}}} || The color to use in between the dashes (optional) || ''Color'' ||  -  ||
+|| {{{dashes-background-opacity}}} || Opacity value for the dashes background || ''Opacity'' ||  value of {{{opacity}}}  ||
+|| {{{linecap}}} || Shape at the end of the line (see [https://www.w3.org/TR/SVG/painting.html#StrokeLinecapProperty here]) || {{{none}}}, {{{round}}}, {{{square}}} ||  {{{none}}}  ||
+|| {{{linejoin}}} || Shape at the line corners || {{{round}}}, {{{miter}}}, {{{bevel}}} ||  {{{round}}}  ||
+|| {{{miterlimit}}}                                   || Applies for {{{linejoin: miter}}}. Sets the maximum overshoot when line segments meet at a very small angle || ''Number'' (>= 1.0) ||  10.0  ||
+|| {{{offset}}} || Move line to the left or right (when looking in way direction). This could be used to draw multiple lanes for one way or mark left and right side of a way differently. || ''Number'' (positive value moves line to the left, negative to the right) ||  0  ||
+|| {{{text-position}}} || set to {{{line}}}, if text should be drawn along the line || {{{line}}}, {{{center}}} ||  -  ||
+|| {{{text-...}}}, {{{font-...}}} ||||||  general text & font properties  ||
+|| `repeat-image` || repeated image along a line ''[since 5801]'' || ''Image'' ||  -  ||
+|| `repeat-image-width` || Width of the image (optional, see `icon-width`) ''[since 5811]'' || ''Number'' ||  -  ||
+|| `repeat-image-height` || Height of the image (optional) ''[since 5811]'' || ''Number'' ||  -  ||
+|| `repeat-image-align` || Alignment of the image. Top-, bottom edge or the (horizontal) center line of the image will be along the line ''[since 5801]'' || `top`, `center`, `bottom` ||  `center`  ||
+|| `repeat-image-offset` || Offset from the line ''[since 5801]'' || ''Number'' ||  0  ||
+|| `repeat-image-spacing` || Spacing between repeated images ''[since 5801]'' || ''Number'' ||  0  ||
+|| `repeat-image-phase` || Initial spacing at the beginning of the line ''[since 5812]'' || ''Number'' ||  0  ||
+
+All these properties (except for {{{text-...}}} and {{{font-...}}}) exist also with the {{{casing-}}} prefix. The casing is a second independent line element, that is drawn below the normal line and can be used to draw a thin frame around the line in another color.
+||=  '''Key''' =||= '''Description''' =||= '''Value Format''' =||= '''Default Value''' =||
+|| {{{casing-width}}}               || Width of the border on both sides of the main line. In JOSM < 5214: Total width of the casing || ''Width'' (revers to {{{width}}} if relative width is specified) ||  -  ||
+|| {{{casing-color}}} || Casing color || ''Color'' ||  value of {{{fill-color}}} or (if unset) JOSM's default untagged color ({{{#808080}}}) ||
+|| {{{casing-opacity}}} || How transparent the casing is. || ''Opacity'' ||  1.0  ||
+|| {{{casing-}}}... || ... || ... ||  ...  ||
+Similar to {{{casing-}}}, there is also the {{{left-casing-}}} and {{{right-casing-}}} prefix. It draws additional lines to the left and to the right of the main line.
+
+=== Area styles ===
+||=  '''Key''' =||= '''Description''' =||= '''Value Format''' =||= '''Default Value''' =||
+|| {{{fill-color}}} || Color in which to fill the area. Until 11700, the alpha component was set to 50 to create a transparency effect. || ''Color'' ||  -  ||
+|| {{{fill-image}}} || Image pattern || ''Image'' ||  -  ||
+|| {{{fill-extent}}} || Set this property, to draw only the outline of the area. The number specifies, how far to fill from the border of the area towards the center. (If unset, the area will be filled completely) ''[since 9008]'' || ''Number'' ||  -  ||
+|| {{{fill-opacity}}} || How transparent the fill is; applies to both color and image || ''Opacity'' || 0.2 ''[since 11700, 1.0 before that]'' (can be changed with the {{{mappaint.fillalpha}}} and {{{mappaint.fill-image-alpha}}} preferences)  ||
+|| {{{text-position}}} || set to {{{center}}}, if text should be drawn in the center of the area. Set to {{{inside}}} to place the text completely inside the area (since r11722). || {{{line}}}, {{{center}}}, {{{inside}}} ||  -  ||
+|| {{{text-...}}}, {{{font-...}}} ||||||  general text & font properties  ||
+Required properties to create an Area style: {{{fill-color}}} or {{{fill-image}}} 
+
+
+=== Text & Font properties ===
+{{{#!th align=left valign=top 
+'''Key'''
+}}}
+{{{#!th align=left valign=top
+'''Description'''
+}}}
+{{{#!th align=left valign=top
+'''Value Format'''
+}}}
+{{{#!th align=left valign=top
+'''Default Value'''
+}}}
+|-------------------------------------------------------------------------------
+{{{#!td align=left  valign=top
+{{{text}}}  
+}}}
+{{{#!td align=left  valign=top
+How to find the label text. No label is displayed, unless this instruction is present.
+}}}
+{{{#!td align=left  valign=top
+{{{auto}}}
+   Derive the text automatically. The default name tags are: "{{{name:}}}"+''<LANG>'', "{{{name}}}", "{{{int_name}}}", "{{{ref}}}", "{{{operator}}}", "{{{brand}}}" and "{{{addr:housenumber}}}". 
+
+   Configure a list of tag names in the preference "{{{mappaint.nameOrder}}}" in order to change this list. (After changing the list, a restart of JOSM is required.)
+
+''String''
+   Denotes the key of the tag whose value is used as text.
+
+''Expressions''
+  You can enter an expression to compute the text to be displayed. Examples:
+  * {{{eval("this is a static text")}}} - renderes a static text
+  * {{{eval(concat(tag("first"), "-", tag("second")))}}} - displays the concatenated tags "first" and "second" 
+
+{{{""}}}
+   To delete a previous set text.
+}}}
+{{{#!td align=center  valign=top
+-
+}}}
+|-------------------------------------------------------------------------------
+|| {{{text-color}}} || the text color || ''Color'' ||  {{{white}}} for lines and nodes, {{{#c0c0c0}}} for areas (JOSM "{{{text}}}" and "{{{areatext}}}" color preferences) ||
+|| {{{text-opacity}}} || how transparent the text is || ''Opacity'' ||  1.0  ||
+|| {{{text-offset-x}}} || shift the text horizontally, (not supported for text along line) || ''Number'' ||  0  ||
+|| {{{text-offset-y}}} (can also be written as {{{text-offset}}})  || shift the text vertically, positive values shift the text in upwards direction  || ''Number'' ||  0  ||
+|| {{{text-halo-radius}}} || size of text background border (to make text visible on background with a similar color) || ''Number'' ||  -  ||
+|| {{{text-halo-color}}} || color of the text halo || ''Color'' ||  complement of the text color  ||
+|| {{{text-halo-opacity}}} || transparency for the text halo || ''Opacity'' ||  1.0  ||
+|| {{{font-family}}} || font family || ''String'' ||  "Helvetica"[[br]](JOSM preference "mappaint.font")  ||
+|| {{{font-size}}} || font size || ''Number'' ||  8[[br]](JOSM preference "mappaint.fontsize")  ||
+|| {{{font-weight}}} || bold or not || {{{bold}}}, {{{normal}}} ||  {{{normal}}}  ||
+|| {{{font-style}}} || italic or not || {{{italic}}}, {{{normal}}} ||  {{{normal}}}  ||
+
+'' '''Width''' ''
+ - 14.0 (any positive number)
+ - {{{default}}} (use JOSM's default line width, which is 2, but can be configured) 
+ - {{{thinnest}}} (draws the line as thin as possible) 
+ - +3 (with plus sign in front) adds the amount to the width on the default layer. This applies only for styles that are not on the default layer, e.g. highlights. Another way to write this would be {{{prop("width","default")+3}}}. For {{{casing-width}}}, this refers to the {{{width}}} value on the same layer.
+
+'' '''Image''' ''
+ See [wiki:Help/Styles/Images].
+
+'' '''Color''' ''
+ * named color as found in [https://www.w3.org/TR/css3-color/#svg-color this] list
+ * html style: '''{{{#RRGGBB}}}''', '''{{{#RGB}}}''', '''{{{#RRGGBBAA}}}'''
+ * '''{{{rgb(/*r*/, /*g*/, /*b*/)}}}''' - rgb value with arguments from 0.0 to 1.0
+ * '''{{{rgba(/*r*/, /*g*/, /*b*/, /*alpha*/)}}}''' - rgb value with alpha
+ * '''{{{hsb_color(/*hue*/, /*saturation*/, /*brightness*/)}}}''' - color from HSB color space
+
+'' '''Opacity''' ''
+ * from 0.0 (transparent) to 1.0 (opaque)
+
+'' '''String''' ''
+ * any character sequence, in quotes, e.g. {{{"images/fill.png"}}}. If the string is an identifier, quotes are optional. (Quote and backslash sign can be escaped.)
+
+'' '''Number''' ''
+ * integer or floating point (in simple form e.g. 0.3). In general can be negative, but most properties do not support negative numbers
+ * has a special meaning if you put a "+" sign in front (relative width)
+
+== Eval expressions ==
+
+
+See [/doc/org/openstreetmap/josm/gui/mappaint/mapcss/ExpressionFactory.Functions.html#method_summary Javadoc of Functions] for the up-to-date list of functions supported by JOSM's MapCSS implementation.
+
+ +, -, *, /::
+  arithmetic operations
+ ||, &&, !::
+  boolean operations
+ <, >, <=, >=, ==::
+  comparison operators
+ asin, atan, atan2, ceil, cos, cosh, exp, floor, log, max, min, random, round, signum, sin, sinh, sqrt, tan, tanh::
+  the usual meaning, [https://download.oracle.com/javase/8/docs/api/java/lang/Math.html details]
+ cond(b, fst, snd)::
+ b ? fst : snd::
+  if ('''b''') then '''fst''' else '''snd'''
+ list(a, b, ...)::
+  create list of values, e.g. for the {{{dashes}}} property
+ get(lst, n)::
+  get the ''n''th element of the list ''lst'' (counting starts at 0) [''since 5699'']
+ split(sep, str)::
+  splits string ''str'' at occurrences of the separator string ''sep'', returns a list [''since 5699'']
+ prop(''p_name'')::
+  value of the property ''p_name'' of the current layer, e.g. prop({{{"width"}}})
+ prop(''p_name'', ''layer_name'')::
+  property from the layer ''layer_name''
+ is_prop_set(''p_name'')::
+  true, if property ''p_name'' is set for the current layer
+ is_prop_set(''p_name'', ''layer_name'')::
+  true, if property ''p_name'' is set for the layer ''layer_name''
+ tag(''key_name'')::
+  get the value of the key ''key_name'' from the object in question
+ parent_tag(''key_name'')::
+  get the value of the key ''key_name'' from the object's parent
+ parent_tags(''key_name'')::
+  returns all parent's values for the key ''key_name'' as a list ordered by a natural ordering [''since 8775'']
+ has_tag_key(''key_name'')::
+  true, if the object has a tag with the given key
+ rgb(''r'', ''g'', ''b'')::
+  create color value (arguments from 0.0 to 1.0)
+ hsb_color(''h'', ''s'', ''b'')::
+  create color from hue, saturation and brightness (arguments from 0.0 to 1.0) [''since 6899'']
+ red(''clr''), green(''clr''), blue(''clr'')::
+  get value of color channels in rgb color model
+ alpha(''clr'')::
+  get the alpha value of the given color [''since 6749'']
+ length(''str'')::
+  length of a string
+ count(''lst'')::
+  length of a list, i.e., counts its elements [''since 7162'']
+ length(''lst'')::
+  length of a list [''since 5699''] – deprecated ''since 7162''
+ any(obj1, obj2, ...)::
+  returns the first object which is not null (formerly coalesce, [''since 7164''])
+ concat(''str1'', ''str2'', ...)::
+  assemble the strings to one
+ join(''sep'', ''str1'', ''str2'', ...)::
+  join strings, whith ''sep'' as separator [''since 6737'']
+ join_list(''sep'', ''list_name'')::
+   joins the elements of the list ''list_name'' to one string separated by the separator ''sep'' [''since 8775'']
+ upper(''str'')::
+   converts string to upper case [''since 11756'']
+ lower(''str'')::
+   converts string to lower case [''since 11756'']
+ trim(''str'')::
+   remove leading and trailing whitespace from string [''since 11756'']
+ JOSM_search("...")::
+  true, if JOSM search applies to the object
+ tr(str, arg0, arg1, ...)::
+  translate from English to the current language (only for strings in the JOSM user interface) [''since 6506'']
+ regexp_test(regexp, string)::
+  test if ''string'' matches pattern ''regexp'' [''since 5699'']
+ regexp_test(regexp, string, flags)::
+  test if ''string'' matches pattern ''regexp''; flags is a string that may contain "i" (case insensitive), "m" (multiline) and "s" ("dot all") [''since 5699'']
+ regexp_match(regexp, string)::
+  Tries to match ''string'' against pattern ''regexp''. Returns a list of capture groups in case of success. The first element (index 0) is the complete match (i.e. ''string''). Further elements correspond to the bracketed parts of the regular expression. [''since 5701'']
+ regexp_match(regexp, string, flags)::
+  Tries to match ''string'' against pattern ''regexp''. Returns a list of capture groups in case of success. The first element (index 0) is the complete match (i.e. ''string''). Further elements correspond to the bracketed parts of the regular expression. Flags is a string that may contain "i" (case insensitive), "m" (multiline) and "s" ("dot all") [''since 5701'']
+ substring(str, idx)::
+  return the substring of ''str'', starting at index ''idx'' (0-indexed) [''since 6534'']
+ substring(str, start, end)::
+  return the substring of ''str'', starting at index ''start'' (inclusive) up to ''end'' (exclusive) (0-indexed) [''since 6534'']
+ replace(string, old, new)::
+   Replaces any occurrence of the substring ''old'' within the string ''string'' with the text ''new'' 
+ osm_id()::
+  returns the OSM id of the current object [''since 5699'']
+ parent_osm_id()::
+  returns the OSM id of the object's parent (matched by child selector) [''since 13094'']
+ URL_encode(str)::
+  [https://en.wikipedia.org/wiki/Percent-encoding percent-encode] a string. May be useful for data URLs [''since 6805'']
+ URL_decode(str)::
+  [https://en.wikipedia.org/wiki/Percent-encoding percent-decode] a string. [''since 11756'']
+ XML_encode(str)::
+  escape special characters in xml. E.g. {{{<}}} becomes {{{&lt;}}}, other special characters: {{{>}}}, {{{"}}}, {{{'}}}, {{{&}}}, {{{\n}}}, {{{\t}}} and {{{\r}}} [''since 6809'']
+ CRC32_checksum(''str'')::
+  calculate the CRC32 checksum of a string (result is an integer from 0 to 2^32^-1) [''since 6908'']
+ is_right_hand_traffic()::
+  Check if there is left-hand or right-hand traffic at the current location. [''since 7193'']
+ number_of_tags()::
+  returns the number of tags for the current OSM object [''since 7237'']
+ print(o)::
+  prints a string representation of `o` to the command line (for debugging) [''since 7237'']
+ println(o)::
+  prints a string representation of `o` to the command line, followed by a new line (for debugging) [''since 7237'']
+ JOSM_pref(''key'', ''default'')::
+  Get value from the JOSM advanced preferences. This way you can offer certain options to the user and make the style customizable. It works with strings, numbers, colors and boolean values. [[br]][This function exists since version 3856, but with some restrictions. `JOSM_pref` always returns a string, but in version 7237 and earlier, the automatic conversion of string to boolean and color was not working. You can use the following workarounds for boolean values and color in version 7237 and earlier: `cond(JOSM_pref("myprefkey", "true")="true", "X", "O")` and `html2color(JOSM_pref("mycolor", "#FF345611"))`. These explicit conversions should be no longer necessary in version 7238 and later. Automatic conversion to a number works in any version.]
+ setting()::
+  to use a [[Help/Styles/MapCSSImplementation#Stylesettings|style setting]] [''since 7450'']
+ degree_to_radians()::
+  returns a in degree given direction in radians [''since 8260'']
+ cardinal_to_radians()::
+  returns a cardinal direction in radians [''since 8260'']
+ waylength()::
+  returns the length of the way in metres [''since 8253'']
+ areasize()::
+  returns the area of a closed way in square meters [''since 8253'']
+ at(lat,lon)::
+  returns true if the object centroid lies at given ''lat''/''lon'' coordinates, e.g. to check for nodes at "null island" `node[at(0.0,0.0)]` [''since 12514'']
+
+
+=== Examples ===
+
+* circle symbol for house number with size depending of the number of digits
+{{{
+#!mapcss
+node[addr:housenumber] { 
+    symbol-shape: circle; 
+    symbol-size: eval((min(length(tag("addr:housenumber")), 3) * 5) + 3); 
+    symbol-fill-color: #B0E0E6; 
+
+    text: "addr:housenumber"; 
+    text-anchor-horizontal: center; 
+    text-anchor-vertical: center; 
+    text-offset-x: -1; 
+    text-offset-y: -1; }
+    
+node[addr:housenumber]::hn_casing { 
+    z-index: -100; 
+    symbol-shape: circle; 
+    symbol-size: +2; 
+    symbol-fill-color: blue; 
+}
+}}}
+* invert colors
+{{{
+#!mapcss
+*::* {
+    color: eval(rgb(1 - red(prop(color)), 1 - green(prop(color)), 1 - blue(prop(color))));
+    fill-color: eval(rgb(1 - red(prop(fill-color)), 1 - green(prop(fill-color)), 1 - blue(prop(fill-color))));
+}
+}}}
+* random stuff
+{{{
+#!mapcss
+way {
+    width: eval(random() * 20);
+    color: eval(rgb(random(), random(), random()));
+}
+}}}
+
+* regexp matching example: change "nameXXXsubname" to "name::subname"
+{{{
+#!mapcss
+*[name=~/.+XXX.+/] 
+{
+    _match: regexp_match("(.+?)XXX(.+)", tag("name"));
+    text: concat(get(prop("_match"),1), "::", get(prop("_match"),2));
+}
+}}}
+
+* paint buildings in different colors according to street in the address tags
+{{{
+#!mapcss
+area[building][addr:street] {
+    fill-color: hsb_color(CRC32_checksum(tag("addr:street"))/4294967296.0, 0.9, 0.7);
+    fill-opacity: 0.8;
+}
+}}}
+
+
+== Compatibility notes ==
+=== MapCSS 0.2 ===
+
+==== Grammar ====
+
+ * {{{way[oneway=yes]}}} does not have any magic, you can use {{{way[oneway?]}}} instead
+ * no {{{@import}}}
+ * JOSM does not require {{{eval(...)}}} to be wrapped around expressions, but for compatibility with other MapCSS implementations you should write it out.
+
+==== Properties ====
+At the moment, JOSM does ''not'' support the following properties: 
+ line: ::
+  {{{image}}}
+ label: ::
+  {{{font-variant, text-decoration, text-transform, max-width}}}
+ shield: ::
+  not supported
+
+=== Halcyon (Potlatch 2) ===
+
+ * Text label is placed in the center of the icon. For compatibility with Halcyon put
+{{{
+#!mapcss
+node { text-anchor-vertical: center; text-anchor-horizontal: center; }
+}}}
+ at the beginning of your style sheet.
+ * standard z-index in Halcyon is 5, but it is 0 in JOSM
+ * '''{{{image: circle;}}}''' corresponds to '''{{{symbol-shape: circle;}}}'''
+
+=== Kothic ===
+
+ * Kothic has support for eval, which probably differs from JOSM's eval.
+ * Kothic understands units, whereas JOSM always calculates in pixel.
+ * The extrusion features are not available in JOSM
+
+=== Ceyx ===
+
+ * seems to have {{{[tunnel=1]}}} instead of {{{[tunnel=yes]}}} (Halcyon) or {{{[tunnel?]}}} (JOSM)
+
+== Media queries [''since 6970'']  (deprecated) ==
+
+{{{#!td style="background-color: #faa"
+Note: media queries are deprecated. You should use @supports rules instead (see above).
+}}}
+Media queries are used to skip a section of the style under certain conditions. Typically you want to use a feature which is introduced in a newer version of JOSM, but like to have a fall back style for users of older JOSM clients. Example:
+{{{
+#!mapcss
+@media (min-josm-version: 9789) {
+    way[highway] {
+        width: 4;
+        color: orange;
+    }
+    /* fancy new stuff */
+    /* ... */
+}
+
+@media (max-josm-version: 9788) {
+    way[highway] {
+        width: 4;
+        color: blue;
+    }
+    /* fall back mode, using more simple features */
+    /* ... */
+}
+}}}
+
+The syntax closely matches the official [https://www.w3.org/TR/css3-mediaqueries/#syntax css syntax]. The following conditions are supported:
+
+{{{#!th
+'''Media condition'''
+}}}
+{{{#!th
+'''Description'''
+}}}
+|-
+{{{#!td
+(min-josm-version: ''<number>'')
+}}}
+{{{#!td
+Only include {{{@media}}} section when the current version of JOSM is greater than or equal to the specified number.
+}}}
+|-
+{{{#!td
+(max-josm-version: ''<number>'')
+}}}
+{{{#!td
+Only include {{{@media}}} section when the current version of JOSM is lower than or equal to the specified number.
+}}}
+|-
+{{{#!td
+(user-agent: ''<string>'')
+}}}
+{{{#!td
+Only include {{{@media}}} section when the name of the editor / renderer matches the given string. In JOSM, the only accepted value is {{{josm}}}. 
+}}}
+
+Conditions can be combined with {{{and}}}:
+
+{{{
+#!mapcss
+@media (min-josm-version: 6970) and (max-josm-version: 7014) {
+ /* only for JOSM versions 6970 to 7014 */
+}
+}}}
+
+Multiple combined conditions can be chained with a comma (logical ''or''):
+
+{{{
+#!mapcss
+@media (min-josm-version: 6970) and (max-josm-version: 7014), (user-agent: myEditor) {
+  /* for JOSM version 6970 to 7014 and for the editor called "myEditor" */
+}
+}}}
+
+Since media queries are only supported in JOSM 6970 and later, you should also specify this as minimum JOSM version in the meta selector:
+
+{{{
+#!mapcss
+meta {
+    min-josm-version: "6970"; /* This style uses media queries */
+    /* ... */
+}
+}}}
+
+
+{{{#!comment
+There is also the {{{not}}} keyword (see the linked css doc for details).
+This is implemented, but probably not very useful. Feel free to add documentation.
+}}}