Sure, that's why I think it is a bad topic for a tutorial.
The programming style is cool, but it would be better if you implemented another algorithm, something that could be used in a real world app, or at least warn the readers they should never get credit card numbers in their app (unless they are building a bank..)
The intended takeaways here are checksums and the functional-style implemention - definitely not intended as an introduction to financial processing.
Sure, that's why I think it is a bad topic for a tutorial.
The programming style is cool, but it would be better if you implemented another algorithm, something that could be used in a real world app, or at least warn the readers they should never get credit card numbers in their app (unless they are building a bank..)
Fair point!