protected override Delegate GetGetterCore(IChannel ch, IRow input, int iinfo, out Action disposer) { Host.AssertValueOrNull(ch); Host.AssertValue(input); Host.Assert(0 <= iinfo && iinfo < Infos.Length); disposer = null; var getSrc = GetSrcGetter <DvText>(input, iinfo); return(_valueMap.GetGetter(getSrc)); }