This algorith fails on '49927398716' in my test case. That was the code given on the LUHN-10 website. It comes up with a sum of 62 when it should be a sum of 70 per the original algorithm.

I am curious if you can explain how the 

($sum += chop $number) ... ($sum += $LUHN10_map[chop $number]) while $
+number ne '';

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logic works. I just (like 1 minute ago) learned about the bi-stable operator.

While typing this, I figured out why this failed my test case. The call to '...' is persistant across subroutine calls. In my test case, I use 

('125', '49927398716', '4992739872')

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and it failed on '49927398716'. When I used 
('125', '49927398716', '49927398716','4992739872')

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it failed on the 1st '49927398716' and on '4992739872' so I can only assume this operator maintains its state.

UPDATE: This also fails on '620' since the bi-stable does not flip state if the side that is being evaluated returns false(or 0). So a number ending in '0' will not be processed correctly.

In reply to Re: (dkubb) Re: (2) YAL10CI (Yet Another LUHN-10 Checksum Implementation) by johannz
in thread YAL10CI (Yet Another LUHN-10 Checksum Implementation) by larryl

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