Function numberkit::is_digit

pub fn is_digit<S>(text: S, allow_negative: bool) -> bool where
    S: AsRef<OsStr>, 

Check string is digit

Example

assert_eq!(true, numberkit::is_digit("2", false));
assert_eq!(false, numberkit::is_digit("-2", false));
assert_eq!(false, numberkit::is_digit("0.2", false));