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luhn-generator

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A generator of numbers that passes the validation of Luhn algorithm or Luhn formula, also known as the 'modulus 10' or 'mod 10' algorithm

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var SetCache = require('./_SetCache'), arrayIncludes = require('./_arrayIncludes'), arrayIncludesWith = require('./_arrayIncludesWith'), cacheHas = require('./_cacheHas'), createSet = require('./_createSet'), setToArray = require('./_setToArray'); /** Used as the size to enable large array optimizations. */ var LARGE_ARRAY_SIZE = 200; /** * The base implementation of `_.uniqBy` without support for iteratee shorthands. * * @private * @param {Array} array The array to inspect. * @param {Function} [iteratee] The iteratee invoked per element. * @param {Function} [comparator] The comparator invoked per element. * @returns {Array} Returns the new duplicate free array. */ function baseUniq(array, iteratee, comparator) { var index = -1, includes = arrayIncludes, length = array.length, isCommon = true, result = [], seen = result; if (comparator) { isCommon = false; includes = arrayIncludesWith; } else if (length >= LARGE_ARRAY_SIZE) { var set = iteratee ? null : createSet(array); if (set) { return setToArray(set); } isCommon = false; includes = cacheHas; seen = new SetCache; } else { seen = iteratee ? [] : result; } outer: while (++index < length) { var value = array[index], computed = iteratee ? iteratee(value) : value; value = (comparator || value !== 0) ? value : 0; if (isCommon && computed === computed) { var seenIndex = seen.length; while (seenIndex--) { if (seen[seenIndex] === computed) { continue outer; } } if (iteratee) { seen.push(computed); } result.push(value); } else if (!includes(seen, computed, comparator)) { if (seen !== result) { seen.push(computed); } result.push(value); } } return result; } module.exports = baseUniq;