reorderImpl
internal fun <T, C, V : Comparable<V>> Reorder<T, C>.reorderImpl(desc: Boolean, expression: ColumnExpression<C, V>, unwrapSingleColumnGroup: Boolean = true): DataFrame<T>
Parameters
unwrapSingleColumnGroup
when true and Reorder.columns selects exactly one column group, the nested columns of that group are reordered instead of the group itself. reorderColumnsBy(atAnyDepth = false) passes false: it must reorder only the top-level columns, even when the only top-level column is a column group. The value is passed on to the dataframes of frame columns.