# Module type Comparable.With_zero

    module type With_zero = Comparable_intf.With_zero

    type t

    val validate_positive : t Validate.check

    val validate_non_negative : t Validate.check

    val validate_negative : t Validate.check

    val validate_non_positive : t Validate.check

    val is_positive : t -> bool

    val is_non_negative : t -> bool

    val is_negative : t -> bool

    val is_non_positive : t -> bool