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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'), arrayMap = require('./_arrayMap'), baseUnary = require('./_baseUnary'), cacheHas = require('./_cacheHas'); /* Built-in method references for those with the same name as other `lodash` methods. */ var nativeMin = Math.min; /** * The base implementation of methods like `_.intersection`, without support * for iteratee shorthands, that accepts an array of arrays to inspect. * * @private * @param {Array} arrays The arrays to inspect. * @param {Function} [iteratee] The iteratee invoked per element. * @param {Function} [comparator] The comparator invoked per element. * @returns {Array} Returns the new array of shared values. */ function baseIntersection(arrays, iteratee, comparator) { var includes = comparator ? arrayIncludesWith : arrayIncludes, length = arrays[0].length, othLength = arrays.length, othIndex = othLength, caches = Array(othLength), maxLength = Infinity, result = []; while (othIndex--) { var array = arrays[othIndex]; if (othIndex && iteratee) { array = arrayMap(array, baseUnary(iteratee)); } maxLength = nativeMin(array.length, maxLength); caches[othIndex] = !comparator && (iteratee || (length >= 120 && array.length >= 120)) ? new SetCache(othIndex && array) : undefined; } array = arrays[0]; var index = -1, seen = caches[0]; outer: while (++index < length && result.length < maxLength) { var value = array[index], computed = iteratee ? iteratee(value) : value; value = (comparator || value !== 0) ? value : 0; if (!(seen ? cacheHas(seen, computed) : includes(result, computed, comparator) )) { othIndex = othLength; while (--othIndex) { var cache = caches[othIndex]; if (!(cache ? cacheHas(cache, computed) : includes(arrays[othIndex], computed, comparator)) ) { continue outer; } } if (seen) { seen.push(computed); } result.push(value); } } return result; } module.exports = baseIntersection;