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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 IS_PURE = require('../internals/is-pure'); var anObject = require('../internals/an-object'); var aFunction = require('../internals/a-function'); var getMapIterator = require('../internals/get-map-iterator'); var iterate = require('../internals/iterate'); // `Map.prototype.reduce` method // https://github.com/tc39/proposal-collection-methods $({ target: 'Map', proto: true, real: true, forced: IS_PURE }, { reduce: function reduce(callbackfn /* , initialValue */) { var map = anObject(this); var iterator = getMapIterator(map); var noInitial = arguments.length < 2; var accumulator = noInitial ? undefined : arguments[1]; aFunction(callbackfn); iterate(iterator, function (key, value) { if (noInitial) { noInitial = false; accumulator = value; } else { accumulator = callbackfn(accumulator, value, key, map); } }, { AS_ENTRIES: true, IS_ITERATOR: true }); if (noInitial) throw TypeError('Reduce of empty map with no initial value'); return accumulator; } });