namespace Microsoft.CodeAnalysis.FlowAnalysis.DataFlow
{
    public abstract class DataFlowOperationVisitor<TAnalysisData, TAnalysisContext, TAnalysisResult, TAbstractAnalysisValue> : ?
        where TAnalysisData, AbstractAnalysisData!
        where TAnalysisContext, AbstractDataFlowAnalysisContext<TAnalysisData!, TAnalysisContext!, TAnalysisResult!, TAbstractAnalysisValue>!
        where TAnalysisResult, class, IDataFlowAnalysisResult<TAbstractAnalysisValue>!
    {
        protected virtual TAbstractAnalysisValue ComputeAnalysisValueForReferenceOperation(?! operation, TAbstractAnalysisValue defaultValue);
    }
}