http://snippets.dzone.com/posts Thu, 24 Jul 2008 08:46:22 GMT DZone Snippets: card code http://snippets.dzone.com/posts/show/1147 <code> <br />luhn: func [ ; tested out OK. <br /> card-num [string!] <br /> /local cksum flag val <br />] [ <br /> cksum: 0 <br /> flag: even? length? card-num <br /> foreach digit card-num [ <br /> val: to integer! form digit <br /> if flag [ <br /> val: val * 2 <br /> if val > 9 [val: val - 9] <br /> ; - alt - <br /> ;val: pick [0 2 4 6 8 1 3 5 7 9] val + 1 <br /> ] <br /> cksum: cksum + val <br /> flag: not flag <br /> ] <br /> print cksum <br /> 0 = remainder cksum 10 <br />] <br /> <br />;print luhn "4005550000000019" <br /></code> Fri, 13 Jan 2006 04:13:03 GMT http://snippets.dzone.com/posts/show/1147 gregg.irwin (Gregg Irwin)