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));
}