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# Bidi-map
A library that extends native
[ES6 Map](https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Map)
to bi-directional map.

## Install
```
npm install bidi-map
```

## Usage
```js
const BidiMap = require('bidi-map');

const bidiMap = new BidiMap([
  [1, 'test'],
  ['foo', 'bar'],
]);

bidiMap instanceof BidiMap; // true
bidiMap instanceof Map; // true

bidiMap.get(1); // "test"
bidiMap.has('foo'); // true
bidiMap.exists('bar'); // true
bidiMap.getKeyOf('test'); // 1

const key = Symbol('unique');
bidiMap.set(key, 'test');
bidiMap.getKeysOf('test'); // [1, key]
```

## API Reference
  A Bidirectional Map


* [bidi-map](#module_bidi-map)
    * [BidiMap](#exp_module_bidi-map--BidiMap) ⇐ <code>Map</code> ⏏
        * [new BidiMap([iterable])](#new_module_bidi-map--BidiMap_new)
        * [.count](#module_bidi-map--BidiMap+count) : <code>number</code>
        * [.set(key, value)](#module_bidi-map--BidiMap+set) ⇒ <code>Map.&lt;K, V&gt;</code>
        * [.exists(value)](#module_bidi-map--BidiMap+exists) ⇒ <code>boolean</code>
        * [.getKeyOf(value)](#module_bidi-map--BidiMap+getKeyOf) ⇒ <code>K</code>
        * [.getKeysOf(value)](#module_bidi-map--BidiMap+getKeysOf) ⇒ <code>Array.&lt;K&gt;</code>
        * [.delete(key)](#module_bidi-map--BidiMap+delete) ⇒ <code>boolean</code>
        * [.clear()](#module_bidi-map--BidiMap+clear) ⇒ <code>undefined</code>

<a name="exp_module_bidi-map--BidiMap"></a>

### BidiMap ⇐ <code>Map</code> ⏏
**Kind**: Exported class  
**Extends**: <code>Map</code>  
**Template**: K, V  
<a name="new_module_bidi-map--BidiMap_new"></a>

#### new BidiMap([iterable])
Create a new instance of the bidirectional-map


| Param | Type | Description |
| --- | --- | --- |
| [iterable] | <code>Iterable.&lt;Array&gt;</code> | An iterable object |

<a name="module_bidi-map--BidiMap+count"></a>

#### bidiMap.count : <code>number</code>
Get the number of differed values in this map

**Kind**: instance property of [<code>BidiMap</code>](#exp_module_bidi-map--BidiMap)  
**Read only**: true  
<a name="module_bidi-map--BidiMap+set"></a>

#### bidiMap.set(key, value) ⇒ <code>Map.&lt;K, V&gt;</code>
Inherits from `Map.set` method.

**Kind**: instance method of [<code>BidiMap</code>](#exp_module_bidi-map--BidiMap)  

| Param | Type |
| --- | --- |
| key | <code>K</code> | 
| value | <code>V</code> | 

<a name="module_bidi-map--BidiMap+exists"></a>

#### bidiMap.exists(value) ⇒ <code>boolean</code>
Check if the map has the given value.

**Kind**: instance method of [<code>BidiMap</code>](#exp_module_bidi-map--BidiMap)  

| Param | Type | Description |
| --- | --- | --- |
| value | <code>V</code> | The given value |

<a name="module_bidi-map--BidiMap+getKeyOf"></a>

#### bidiMap.getKeyOf(value) ⇒ <code>K</code>
Get the first key of the given value or `undefined` if not exists.

**Kind**: instance method of [<code>BidiMap</code>](#exp_module_bidi-map--BidiMap)  

| Param | Type |
| --- | --- |
| value | <code>V</code> | 

<a name="module_bidi-map--BidiMap+getKeysOf"></a>

#### bidiMap.getKeysOf(value) ⇒ <code>Array.&lt;K&gt;</code>
Get the all the keys of the given value.

**Kind**: instance method of [<code>BidiMap</code>](#exp_module_bidi-map--BidiMap)  

| Param | Type |
| --- | --- |
| value | <code>V</code> | 

<a name="module_bidi-map--BidiMap+delete"></a>

#### bidiMap.delete(key) ⇒ <code>boolean</code>
Inherits from `Map.delete` method.

**Kind**: instance method of [<code>BidiMap</code>](#exp_module_bidi-map--BidiMap)  

| Param | Type |
| --- | --- |
| key | <code>K</code> | 

<a name="module_bidi-map--BidiMap+clear"></a>

#### bidiMap.clear() ⇒ <code>undefined</code>
Inherits from `Map.clear` method.

**Kind**: instance method of [<code>BidiMap</code>](#exp_module_bidi-map--BidiMap)  

* * *

&copy; 2017 Moshe Simantov

Licensed under the _Apache License, Version 2.0_.