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chad3814chad3814
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add es6-map compatibility layer
- also cleaned up the formatting for my personal tastes
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‎README.md‎

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HashTable
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=========
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[<img src="https://travis-ci.org/isaacbw/node-hashtable.png?branch=master" />](https://travis-ci.org/isaacbw/node-hashtable)
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Sometimes you need to store so much data in memory that V8 can get a bit clogged up. This Node.js module provides an interface to a native hashmap data structure that exists outside of V8's memory constraints.
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To install, simply:
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Returns the number of key/value pairs in the hash table.
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### `forEach ( cb )`
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### `forEach ( cb, context )`
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`cb` is an iterator function that will be called with each key/value pair like `cb(value, key)`.
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`cb` is an iterator function that will be called with each key/value pair like `cb.call(c, key, value)`, if context is not provided, the global.
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### `keys ()`
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Will return an array of the keys stored in the hashtable.
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### `max_load_factor ()` or `max_load_factor ( factor )`
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Either returns or sets the max load factor of the hash table implementation. This value determines when the hash map is rehashed with a new bucket count. By default it is `1.0`. See [unordered_map#max_load_factor](http://www.cplusplus.com/reference/unordered_map/unordered_map/max_load_factor/)
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"But Chad, what if I want a super fast version of ES6's Map? Isn't this really close?"
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---
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You're right anonymous internet user! Just install HashTable like above, but then use like this:
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var Map = require('hashtable/es6-map');
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var map = new Map();
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map.set('key', {value: 'value'});
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map.set('something', 'else');
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console.log('There are', map.size, 'item(s) in the map');
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iterator = map.entries();
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while (!iterator.done) {
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console.log(iterator.key, '=', iterator.value);
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iterator.next();
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}
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See the official []ES6 Map documentation](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-map-objects)

‎es6-iterator.js‎

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'use strict';
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var ES6Iterator = function (native_map, type) {
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var keys = [];
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var values = [];
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native_map.forEach(function (key, value) {
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keys.push(key);
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values.push(value);
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});
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var idx = 0;
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var iterator = Object.defineProperties({}, {
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done: {
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get: function () {
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return idx >= keys.length;
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},
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enumerable: true
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},
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next: {
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value: function () {
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idx += 1;
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return this;
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},
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enumerable: true
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}
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});
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if (type !== 'key' && type !== 'value') {
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type = 'key+value';
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}
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switch (type) {
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case 'key':
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Object.defineProperty(iterator, 'key', {
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get: function () {
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if (this.done) {
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return undefined;
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}
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return keys[idx];
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},
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enumerable: true
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});
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break;
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case 'value':
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Object.defineProperty(iterator, 'value', {
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get: function () {
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if (this.done) {
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return undefined;
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}
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return values[idx];
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},
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enumerable: true
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});
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break;
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case 'key+value': // default
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Object.defineProperties(iterator, {
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key: {
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get: function () {
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if (this.done) {
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return undefined;
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}
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return keys[idx];
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},
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enumerable: true
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},
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value: {
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get: function () {
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if (this.done) {
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return undefined;
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}
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return values[idx];
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},
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enumerable: true
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}
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});
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break;
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}
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return iterator;
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};
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module.exports = ES6Iterator;

‎es6-map.js‎

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'use strict';
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var HashTable = require('./');
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var makeIterator = require('./es6-iterator');
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var ES6Map = function (iterator) {
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this._native_map = new HashTable();
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if (iterator && iterator.hasOwnProperty('done') && iterator.hasOwnProperty('next') && iterator.hasOwnProperty('key') && iterator.hasOwnProperty('value')) {
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while (!iterator.done) {
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this._native_map.put(iterator.key, iterator.value);
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iterator.next();
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}
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}
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};
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ES6Map.prototype = {
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get: function (key) {
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return this._native_map.get(key);
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},
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has: function (key) {
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return this._native_map.get(key) !== undefined;
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},
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set: function (key, value) {
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return this._native_map.put(key, value);
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},
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delete: function (key) {
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return this._native_map.remove(key);
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},
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forEach: function (cb, ctx) {
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return this._native_map.forEach(function (key, value) {
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return cb.call(ctx, value, key, this);
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}, this);
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},
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clear: function () {
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return this._native_map.clear();
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},
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keys: function () {
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return makeIterator(this._native_map, 'key');
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},
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values: function () {
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return makeIterator(this._native_map, 'value');
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},
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entries: function () {
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return makeIterator(this._native_map, 'key+value');
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}
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};
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Object.defineProperty(ES6Map.prototype, 'size', {
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get: function () {
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return this._native_map.size();
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},
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enumerable: true,
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configurable: true
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});
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module.exports = ES6Map;

‎package.json‎

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{
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"name": "hashtable",
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"version": "0.1.5",
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"version": "0.2.1",
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"description": "Native hashtables for Node.js",
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"main": "./index.js",
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"keywords": [
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"es6-map",
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"es6",
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"hash",
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"map",
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"hashmap",

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