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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 isSymbol = require('./isSymbol'); /** Used as references for the maximum length and index of an array. */ var MAX_ARRAY_LENGTH = 4294967295, MAX_ARRAY_INDEX = MAX_ARRAY_LENGTH - 1; /* Built-in method references for those with the same name as other `lodash` methods. */ var nativeFloor = Math.floor, nativeMin = Math.min; /** * The base implementation of `_.sortedIndexBy` and `_.sortedLastIndexBy` * which invokes `iteratee` for `value` and each element of `array` to compute * their sort ranking. The iteratee is invoked with one argument; (value). * * @private * @param {Array} array The sorted array to inspect. * @param {*} value The value to evaluate. * @param {Function} iteratee The iteratee invoked per element. * @param {boolean} [retHighest] Specify returning the highest qualified index. * @returns {number} Returns the index at which `value` should be inserted * into `array`. */ function baseSortedIndexBy(array, value, iteratee, retHighest) { var low = 0, high = array == null ? 0 : array.length; if (high === 0) { return 0; } value = iteratee(value); var valIsNaN = value !== value, valIsNull = value === null, valIsSymbol = isSymbol(value), valIsUndefined = value === undefined; while (low < high) { var mid = nativeFloor((low + high) / 2), computed = iteratee(array[mid]), othIsDefined = computed !== undefined, othIsNull = computed === null, othIsReflexive = computed === computed, othIsSymbol = isSymbol(computed); if (valIsNaN) { var setLow = retHighest || othIsReflexive; } else if (valIsUndefined) { setLow = othIsReflexive && (retHighest || othIsDefined); } else if (valIsNull) { setLow = othIsReflexive && othIsDefined && (retHighest || !othIsNull); } else if (valIsSymbol) { setLow = othIsReflexive && othIsDefined && !othIsNull && (retHighest || !othIsSymbol); } else if (othIsNull || othIsSymbol) { setLow = false; } else { setLow = retHighest ? (computed <= value) : (computed < value); } if (setLow) { low = mid + 1; } else { high = mid; } } return nativeMin(high, MAX_ARRAY_INDEX); } module.exports = baseSortedIndexBy;