Validates strings and computes check digits using the Luhn algorithm.
Add luhn under [dependencies] in your Cargo.toml:
[dependencies]
luhn = "1.0.1"Use the validator!
luhn::valid("4111111111111111"); // trueAppend check digits to your strings and make them Luhn-valid!
// A string which doesn't validate
let mut s = "11111111".to_string();
assert!(!valid(&s));
// Let's fix that
s.push(luhn::checksum(s.as_bytes()) as char);
assert_eq!(s, "111111118");
assert!(valid(&s));