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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 baseSortedIndexBy = require('./_baseSortedIndexBy'), identity = require('./identity'), isSymbol = require('./isSymbol'); /** Used as references for the maximum length and index of an array. */ var MAX_ARRAY_LENGTH = 4294967295, HALF_MAX_ARRAY_LENGTH = MAX_ARRAY_LENGTH >>> 1; /** * The base implementation of `_.sortedIndex` and `_.sortedLastIndex` which * performs a binary search of `array` to determine the index at which `value` * should be inserted into `array` in order to maintain its sort order. * * @private * @param {Array} array The sorted array to inspect. * @param {*} value The value to evaluate. * @param {boolean} [retHighest] Specify returning the highest qualified index. * @returns {number} Returns the index at which `value` should be inserted * into `array`. */ function baseSortedIndex(array, value, retHighest) { var low = 0, high = array == null ? low : array.length; if (typeof value == 'number' && value === value && high <= HALF_MAX_ARRAY_LENGTH) { while (low < high) { var mid = (low + high) >>> 1, computed = array[mid]; if (computed !== null && !isSymbol(computed) && (retHighest ? (computed <= value) : (computed < value))) { low = mid + 1; } else { high = mid; } } return high; } return baseSortedIndexBy(array, value, identity, retHighest); } module.exports = baseSortedIndex;