public interface Columns<T>
extends ColumnRow<T,Column<? extends T>>
In case no order of the Column instances is explicitly required
(similar to a DB table or a spread sheet, in contrast to a CSV file) then
Column instances are grouped by a Columns set.
Columns provide additional semantics to the Field instances
stored in a Record.
Nested Class Summary
Nested classes/interfaces inherited from interface org.refcodes.struct.Keys