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| import assertString from './util/assertString';
| export default function isLuhnNumber(str) {
| assertString(str);
| var sanitized = str.replace(/[- ]+/g, '');
| var sum = 0;
| var digit;
| var tmpNum;
| var shouldDouble;
| for (var i = sanitized.length - 1; i >= 0; i--) {
| digit = sanitized.substring(i, i + 1);
| tmpNum = parseInt(digit, 10);
| if (shouldDouble) {
| tmpNum *= 2;
| if (tmpNum >= 10) {
| sum += tmpNum % 10 + 1;
| } else {
| sum += tmpNum;
| }
| } else {
| sum += tmpNum;
| }
| shouldDouble = !shouldDouble;
| }
| return !!(sum % 10 === 0 ? sanitized : false);
| }
|
|
