The Modulus 10 algorithm is used to detect accidental input errors in digit sequences such as credit card numbers and bank account numbers.
Check out the wikipedia article for more info.
import Mod10
checkDigit : Result Mod10.Error Int
checkDigit =
Mod10.calculateCheckDigit [1, 2, 3]
isValid : Result Mod10.Error Bool
isValid =
Mod10.hasValidCheckDigit [1, 2, 3, 0]