Used internally.
verify_int(x, min_value = -Inf, max_value = Inf, open = "no")Single logical.
value to check.
single integers (each), lower and upper bounds
between which x should lie.
single character, determines whether min_value and max_value
are excluded or not. Valid values: "no" (= closed interval; min_value
and max_value included; default value), "right", "left", "yes"
(= open interval, min_value and max_value excluded).