/// <contentfrom cref="IXmlMapperFactory.Mapper" />
        public override object Mapper(Type source, Type destination, string name = null)
        {
            var key = Key(source, destination, name);

            if (!Mappers.ContainsKey(key))
            {
                Mappers[key] = Factory.Mapper(source, destination, name);
            }

            return(Mappers[key]);
        }