val round :
?dir:[ `Down | `Nearest | `Up | `Zero ] ->
t ->
to_multiple_of:t ->
t
val round_towards_zero : t -> to_multiple_of:t -> t
val round_down : t -> to_multiple_of:t -> t
val round_up : t -> to_multiple_of:t -> t
val round_nearest : t -> to_multiple_of:t -> t