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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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'use strict'; var toIndexedObject = require('../internals/to-indexed-object'); var toInteger = require('../internals/to-integer'); var toLength = require('../internals/to-length'); var arrayMethodIsStrict = require('../internals/array-method-is-strict'); var arrayMethodUsesToLength = require('../internals/array-method-uses-to-length'); var min = Math.min; var nativeLastIndexOf = [].lastIndexOf; var NEGATIVE_ZERO = !!nativeLastIndexOf && 1 / [1].lastIndexOf(1, -0) < 0; var STRICT_METHOD = arrayMethodIsStrict('lastIndexOf'); // For preventing possible almost infinite loop in non-standard implementations, test the forward version of the method var USES_TO_LENGTH = arrayMethodUsesToLength('indexOf', { ACCESSORS: true, 1: 0 }); var FORCED = NEGATIVE_ZERO || !STRICT_METHOD || !USES_TO_LENGTH; // `Array.prototype.lastIndexOf` method implementation // https://tc39.github.io/ecma262/#sec-array.prototype.lastindexof module.exports = FORCED ? function lastIndexOf(searchElement /* , fromIndex = @[*-1] */) { // convert -0 to +0 if (NEGATIVE_ZERO) return nativeLastIndexOf.apply(this, arguments) || 0; var O = toIndexedObject(this); var length = toLength(O.length); var index = length - 1; if (arguments.length > 1) index = min(index, toInteger(arguments[1])); if (index < 0) index = length + index; for (;index >= 0; index--) if (index in O && O[index] === searchElement) return index || 0; return -1; } : nativeLastIndexOf;