Method addFeatures

www/js/_hyperscript.js:1577–1587

(...featureClasses)

      }
    }
    addFeatures(...featureClasses) {
      for (const FeatureClass of featureClasses) {
        if (!FeatureClass.keyword) {
          throw new Error(`Feature class ${FeatureClass.name} must have a static 'keyword' property`);
        }
        if (!FeatureClass.parse) {
          throw new Error(`Feature class ${FeatureClass.name} must have a static 'parse' method`);
        }
        this.addFeature(FeatureClass.keyword, FeatureClass.parse);
      }
    }
    addFeature(keyword, definition) {
      var featureGrammarType = keyword + "Feature";
      this.#grammar[featureGrammarType] = definition;