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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'); /** Used as the size to enable large array optimizations. */ var LARGE_ARRAY_SIZE = 200; /** * The base implementation of methods like `_.difference` without support * for excluding multiple arrays or iteratee shorthands. * * @private * @param {Array} array The array to inspect. * @param {Array} values The values to exclude. * @param {Function} [iteratee] The iteratee invoked per element. * @param {Function} [comparator] The comparator invoked per element. * @returns {Array} Returns the new array of filtered values. */ function baseDifference(array, values, iteratee, comparator) { var index = -1, includes = arrayIncludes, isCommon = true, length = array.length, result = [], valuesLength = values.length; if (!length) { return result; } if (iteratee) { values = arrayMap(values, baseUnary(iteratee)); } if (comparator) { includes = arrayIncludesWith; isCommon = false; } else if (values.length >= LARGE_ARRAY_SIZE) { includes = cacheHas; isCommon = false; values = new SetCache(values); } outer: while (++index < length) { var value = array[index], computed = iteratee == null ? value : iteratee(value); value = (comparator || value !== 0) ? value : 0; if (isCommon && computed === computed) { var valuesIndex = valuesLength; while (valuesIndex--) { if (values[valuesIndex] === computed) { continue outer; } } result.push(value); } else if (!includes(values, computed, comparator)) { result.push(value); } } return result; } module.exports = baseDifference;