public void Accept(IMetadataVisitor visitor)
        {
            visitor.VisitMetadataStream (this);

            m_header.Accept (visitor);
            if (m_heap != null)
                m_heap.Accept (visitor);
        }

		public void Accept (IMetadataVisitor visitor)
		{
			visitor.VisitMetadataRoot (this);

			m_header.Accept (visitor);
			m_streams.Accept (visitor);

			visitor.TerminateMetadataRoot (this);
		}

 /// <summary>
 /// Calls the visitor.Visit(IModuleReference) method.
 /// </summary>
 public override void DispatchAsReference(IMetadataVisitor visitor) {
   visitor.Visit(this);
 }

 /// <summary>
 /// Calls visitor.Visit(IUnitReference).
 /// </summary>
 public abstract void Dispatch(IMetadataVisitor visitor);

		public override void Accept (IMetadataVisitor visitor)
		{
			visitor.VisitGuidHeap (this);
		}

 public void Dispatch(IMetadataVisitor visitor)
 {
 }

 public void DispatchAsReference(IMetadataVisitor visitor)
 {
     throw new NotImplementedException();
 }

 public abstract void Accept(IMetadataVisitor visitor);

 public void DispatchAsReference(IMetadataVisitor visitor) {
   visitor.Visit((ISpecializedMethodReference)this);
 }

 public void Dispatch(IMetadataVisitor visitor) {
   Contract.Requires(visitor != null);
   throw new NotImplementedException();
 }

 public void DispatchAsReference(IMetadataVisitor visitor)
 {
 }

 void IMetadataExpression.Dispatch(IMetadataVisitor visitor)
 {
     visitor.Visit(this);
 }

 public void Dispatch(IMetadataVisitor visitor)
 {
     _ns.Dispatch(visitor);
 }

 public override void DispatchAsReference(IMetadataVisitor visitor) {
   throw new InvalidOperationException();
 }

 void IReference.Dispatch(IMetadataVisitor visitor)
 {
     throw new NotImplementedException();
 }

		public override void Accept (IMetadataVisitor visitor)
		{
			visitor.VisitUserStringsHeap (this);
		}

 public void Dispatch(IMetadataVisitor visitor)
 {
     throw new System.NotImplementedException();
 }

 public void Dispatch(IMetadataVisitor visitor) {
   visitor.Visit(this);
 }

		public void Accept (IMetadataVisitor visitor)
		{
			visitor.VisitMetadataStreamCollection (this);

			for (int i = 0; i < m_items.Count; i++)
				this [i].Accept (visitor);
		}