private EnumerableExcelPropertyMap <TProperty> GetMultiMapping <TProperty>(MemberInfo member) { if (!member.AutoMapEnumerable(EmptyValueStrategy, out EnumerableExcelPropertyMap <TProperty> mapping)) { throw new ExcelMappingException($"No known way to instantiate type \"{typeof(TProperty)}\". It must be a single dimensional array, be assignable from List<T> or implement ICollection<T>."); } return(mapping); }