> Unfortunately, Algorithm::LUHN supports some odd inputs, like non-numeric strings

Careful, is this algorithm well defined for input >=10 !?!

From the docs:

> For example, Standard & Poor's maps A..Z to 10..35 so the LIST to add these valid characters would be (A, 10, B, 11, C, 12, ...)

provided B=11 is on an odd position, what's the formula now to reduce 2*11?

cross total is 4, but 22-9 =13

and if it's even does 11 stay 11 with cross total 2 or do you take it module 10 hence resulting in 1?

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery FootballPerl is like chess, only without the dice

In reply to Re^10: Faster Luhn Check Digit Calculation? by LanX
in thread Faster Luhn Check Digit Calculation? by kschwab

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