Assembly: Microsoft.VisualStudio.Text.UI (in Microsoft.VisualStudio.Text.UI.dll)
This is a MEF component part, and should be imported as follows:
[Import] IViewClassifierAggregatorService aggregator = null;
The normalized classifications produced by this aggregator are sorted and do not overlap. If a span of text has multiple classifications, based on the original classifier contributions, then in the normalized classification it has a transient classification IClassificationTypeRegistryService that corresponds to all of the original classifications
For more information about classification, see the section "Extending Classification Types and Classification Formats" in Editor Extension Points.