anchor.diff:  }
   
   class CompileFactoryMetadata
  -    implements CompileIdentifierMetadata, CompileMetadataWithIdentifier {
  +    implements
  +        CompileIdentifierMetadata<Function>,
  +        CompileMetadataWithIdentifier {
     Function runtime;
     Function runtimeCallback;
     String name;
  
positive.code:  * Metadata regarding compilation of a type.
   */
  class CompileTypeMetadata
      implements CompileIdentifierMetadata, CompileMetadataWithType {
    Type runtime;
    Function runtimeCallback;
    String name;
  
negative.code:   /// value for the output interpreter.
    ///
    /// Not marked final since tests modify value.
    TRuntime runtime;
  
    /// Same as runtime but evaluates function before using value.
    final Function runtimeCallback;
  