next cycles through sort directions. This is used to determine how to update the sort direction when a header is clicked on.
class_ convert the sort direction and precedence of a column from the sort criteria into a string symbol and a css class respectively in order to display sort information in the table.
indicator returns a symbol that is displayed in the header of the corresponding column, while
class_ returns a css class that is assigned to the header element.
precedence is always a positive integer (i.e. it starts at 1, not 0).
A column that is not in the sort criteria is assigned an
Examples of suitable indicators are:
- "▲" (ascending with priority 1)
- "▲(2)" (ascending with priority 2)
val indicator : t -> precedence:int -> string option
val class_ : t -> precedence:int -> string option