# Module type Flags_intf.Flags

    module type Flags = sig .. end

    module type Make_arg = Flags_intf.Make_arg

    module type S = Flags_intf.S

    val create : bit:int -> Int63.t

`create ~bit:n` creates a flag with the `n`th bit set. `n` must be between 0 and 62.

Typically a flag has one bit set; `create` is useful in exactly those cases. For flags with multiple bits one can either define the Int63.t directly or create it in terms of simpler flags, using `+` and `-`.

    module Make: functor (M : Make_arg) -> S  with type t = Int63.t

`Flags.Make` builds a new flags module.