Add road vehicle height restriction units

README.md

@@ -24,6 +24,7 @@ In addition to identifiers, `country-coder` can provide basic regional informati
 - ☎️ [Telephone Calling Codes](https://en.wikipedia.org/wiki/List_of_country_calling_codes) (+44)
 - 🛣 [Driving Side](https://en.wikipedia.org/wiki/Left-_and_right-hand_traffic) (right, left)
 - 🚗 [Traffic Speed Unit](https://en.wikipedia.org/wiki/Speed_limit#Signage) (km/h, mph)
+- 🚚 [Vehicle Height Unit](https://wiki.openstreetmap.org/wiki/Key:maxheight) (m, ft)
 - 🇪🇺 [European Union Membership](https://en.wikipedia.org/wiki/Member_state_of_the_European_Union)
 
 
@@ -110,6 +111,7 @@ This package is kept intentionally minimal. However, if you find a bug or have a
 * [isInEuropeanUnion](#isInEuropeanUnion)(query: Location | string | number): boolean
 * [driveSide](#driveSide)(query: Location | string | number): string?
 * [roadSpeedUnit](#roadSpeedUnit)(query: Location | string | number): string?
+* [roadHeightUnit](#roadHeightUnit)(query: Location | string | number): string?
 * [callingCodes](#callingCodes)(query: Location | string | number): [string]
 
 ##### Properties
@@ -451,6 +453,32 @@ roadSpeedUnit(pointGeoJSON.geometry);  // returns 'mph' (Britain)
 ```
 
 
+<a name="roadHeightUnit" href="#roadHeightUnit">#</a> <b>roadHeightUnit</b>(query: Location | string | number): string?
+[<>](https://github.com/ideditor/country-coder/blob/master/src/country-coder.ts#L733 "Source")
+
+Returns the unit of length used on vehicle height restriction traffic signs for the given location or identifier, if found.
+
+```js
+roadHeightUnit([0, 51.5]);    // returns 'ft' (Britain)
+roadHeightUnit([6.1, 46.2]);  // returns 'm' (Switzerland)
+roadHeightUnit([0, 90]);      // returns null (North Pole)
+roadHeightUnit('EU');         // returns null
+roadHeightUnit('GB');         // returns 'ft'
+roadHeightUnit('GBR');        // returns 'ft'
+roadHeightUnit('826');        // returns 'ft'
+roadHeightUnit(826);          // returns 'ft'
+roadHeightUnit('Q145');       // returns 'ft'
+roadHeightUnit('🇬🇧');         // returns 'ft'
+roadHeightUnit('UK');         // returns 'ft'
+roadHeightUnit('United Kingdom'); // returns 'ft'
+roadHeightUnit('CH');         // returns 'm'
+
+let pointGeoJSON = { type: 'Feature', geometry: { type: 'Point', coordinates: [0, 51.5] } };
+roadHeightUnit(pointGeoJSON);           // returns 'ft' (Britain)
+roadHeightUnit(pointGeoJSON.geometry);  // returns 'ft' (Britain)
+```
+
+
 <a name="callingCodes" href="#callingCodes">#</a> <b>callingCodes</b>(query: Location | string | number): [string]
 
 Returns the full international calling code prefix of phone numbers for the given location or identifier, if any. All prefixes have a country code, with some also including an area code separated by a space character. These are commonly formatted with a preceding plus sign (e.g. `+1 242`).
@@ -571,6 +599,9 @@ An object containing the attributes of a RegionFeature object.
 - `roadSpeedUnit`: `string`, the speed unit used on traffic signs in this feature
     - `mph`: miles per hour
     - `km/h`: kilometers per hour
+- `roadHeightUnit`: `string`, the length unit used on vehicle height restriction signs in this feature
+    - `ft`: feet and inches
+    - `m`: meters
 - `callingCodes`: `[string]`, the international calling codes for this feature, sometimes including area codes
 
 

scripts/format-json.js

@@ -69,6 +69,7 @@ let featureProperties = [
   'isoStatus',
   'driveSide',
   'roadSpeedUnit',
+  'roadHeightUnit',
   'callingCodes'
 ];
 
@@ -88,6 +89,8 @@ function validateFeature(feature) {
     var name = feature.properties.nameEn;
     if (feature.properties.roadSpeedUnit)
       console.error(name + ' has no geometry but has roadSpeedUnit');
+    if (feature.properties.roadHeightUnit)
+      console.error(name + ' has no geometry but has roadHeightUnit');
     if (feature.properties.driveSide) console.error(name + ' has no geometry but has driveSide');
     if (feature.properties.callingCodes)
       console.error(name + ' has no geometry but has callingCodes');

src/country-coder.ts

@@ -76,6 +76,11 @@ type RegionFeatureProperties = {
   // - `km/h`: kilometers per hour
   roadSpeedUnit: string | undefined;
 
+  // The unit used for road vehicle height restrictions within this feature
+  // - `ft`: feet and inches
+  // - `m`: meters
+  roadHeightUnit: string | undefined;
+
   // The international calling codes for this feature, sometimes including area codes
   // e.g. `1`, `1 340`
   callingCodes: Array<string> | undefined;
@@ -168,6 +173,7 @@ function loadDerivedDataAndCaches(borders) {
 
     // must load attributes only after loading geometry features into `members`
     loadRoadSpeedUnit(feature);
+    loadRoadHeightUnit(feature);
     loadDriveSide(feature);
     loadCallingCodes(feature);
 
@@ -306,6 +312,27 @@ function loadDerivedDataAndCaches(borders) {
     }
   }
 
+  function loadRoadHeightUnit(feature: RegionFeature) {
+    let props = feature.properties;
+    if (feature.geometry) {
+      // only `ft` regions are listed explicitly, else assume `m`
+      if (!props.roadHeightUnit) props.roadHeightUnit = 'm';
+    } else if (props.members) {
+      let vals = Array.from(
+        new Set(
+          props.members
+            .map(function (id) {
+              let member = featuresByCode[id];
+              if (member.geometry) return member.properties.roadHeightUnit || 'm';
+            })
+            .filter(Boolean)
+        )
+      );
+      // if all members have the same value then that's also the value for this feature
+      if (vals.length === 1) props.roadHeightUnit = vals[0];
+    }
+  }
+
   function loadDriveSide(feature: RegionFeature) {
     let props = feature.properties;
     if (feature.geometry) {
@@ -702,6 +729,12 @@ export function roadSpeedUnit(query: Location | string | number): string | null
   return (feature && feature.properties.roadSpeedUnit) || null;
 }
 
+// Returns the road vehicle height restriction unit for the feature matching `query` as a string (`ft` or `m`)
+export function roadHeightUnit(query: Location | string | number): string | null {
+  let feature = smallestOrMatchingFeature(query);
+  return (feature && feature.properties.roadHeightUnit) || null;
+}
+
 // Returns the full international calling codes for phone numbers in the feature matching `query`, if any
 export function callingCodes(query: Location | string | number): Array<string> {
   let feature = smallestOrMatchingFeature(query);