anchor.diff:        );
       }
   
  -    _classPrefixes[annotatedElementSource] ??= [];
  -    _classPrefixes[annotatedElementSource]!.add(classPrefix);
  +    globalData.classPrefixesForLibrary[annotatedElementSource] ??= [];
  +    globalData.classPrefixesForLibrary[annotatedElementSource]!
  +        .add(classPrefix);
   
       return data;
     }
  
positive.code: 
      final classPrefix = data.classPrefix;
  
      if (_classPrefixes[annotatedElementSource]?.contains(classPrefix) ??
          false) {
        throw InvalidGenerationSourceError(
          'Defined a collection with duplicate class prefix $classPrefix.'
  
negative.code:   'package:cloud_firestore_platform_interface/src/geo_point.dart#GeoPoint',
  );
  
  class GlobalData {
    final classPrefixesForLibrary = <Object?, List<String>>{};
  }
  
  @immutable
  class CollectionGenerator
      extends ParserGenerator<GlobalData, Data, Collection> {
    final _collectionTemplates = <Template<CollectionData>>[
      CollectionReferenceTemplate(),
      DocumentReferenceTemplate(),
  