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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 $ = require('../internals/export'); var createIteratorConstructor = require('../internals/create-iterator-constructor'); var requireObjectCoercible = require('../internals/require-object-coercible'); var InternalStateModule = require('../internals/internal-state'); var StringMultibyteModule = require('../internals/string-multibyte'); var codeAt = StringMultibyteModule.codeAt; var charAt = StringMultibyteModule.charAt; var STRING_ITERATOR = 'String Iterator'; var setInternalState = InternalStateModule.set; var getInternalState = InternalStateModule.getterFor(STRING_ITERATOR); // TODO: unify with String#@@iterator var $StringIterator = createIteratorConstructor(function StringIterator(string) { setInternalState(this, { type: STRING_ITERATOR, string: string, index: 0 }); }, 'String', function next() { var state = getInternalState(this); var string = state.string; var index = state.index; var point; if (index >= string.length) return { value: undefined, done: true }; point = charAt(string, index); state.index += point.length; return { value: { codePoint: codeAt(point, 0), position: index }, done: false }; }); // `String.prototype.codePoints` method // https://github.com/tc39/proposal-string-prototype-codepoints $({ target: 'String', proto: true }, { codePoints: function codePoints() { return new $StringIterator(String(requireObjectCoercible(this))); } });