Ascii_table.Column
type 'a t
val create : ?align:Align.t -> ?min_width:int -> ?max_width:int -> ?show:[ `Yes | `No | `If_not_empty ] -> string -> ('a -> string) -> 'a t
creates a column given the header and the to-string function
val create_attr : ?align:Align.t -> ?min_width:int -> ?max_width:int -> ?show:[ `Yes | `No | `If_not_empty ] -> string -> ('a -> Attr.t list * string) -> 'a t
like create, except that the to_string function must provide a list of attributes.