nl_tokens: Create a vector source based on a Mapbox GL styles definition .
pl_tokens: function configureGeojsonSource ( glSource , mapView , baseUrl , wrapX , fetchOptions ) { const use_bbox = ( typeof glSource . data === 'string' && glSource . data . indexOf ( BBOX_STRING ) >= 0 ) ; const vector_src = new VectorSource ( { strategy : use_bbox ? bboxStrategy : allStrategy , loader : getLoaderFunction ( glSource , mapView . getProjection ( ) , baseUrl , fetchOptions ) , useSpatialIndex : <mask> , wrapX : wrapX , } ) ; // GeoJson sources can be clustered but OpenLayers // uses a special source type for that. This handles the // "switch" of source-class. let new_src = vector_src ; if ( glSource . cluster ) { new_src = new ClusterSource ( { source : vector_src , // default the distance to 50 as that's what //  is specified by Mapbox. distance : glSource . clusterRadius ? glSource . clusterRadius : 50 , } ) ; } // seed the vector source with the first update //  before returning it. updateGeojsonSource ( new_src , glSource , mapView , baseUrl , fetchOptions ) ; return new_src ; }