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https://github.com/hedronium/linkedlist.js

A Javascript implementation of the LinkedList
https://github.com/hedronium/linkedlist.js

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A Javascript implementation of the LinkedList

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README 

        
#LinkedList.js

A simple doubly linked list implementation in Javascript.



## Installation

```

npm install linkedlist-js

```



## Usage

require the module...



```javascript

var List = require('linkedlist-js').List;

```



instantiate a List object...

```javascript

var list = new List();



// PUSH!

list.push('HUEHUE');

```



### Traversing the List

#### with each(callback)

```javascript

list.each(function (index, node) {

    console.log(index + ': ' + node.value());

});

```



#### like a badass

```javascript

var node = list.head();



while (node != null) {

    console.log(node.value());

    node = node.next();

}

```



## `List` API

### Adding Nodes

#### push(value)

Creates a node with the value specified, adds it to the end of the list and returns the `Node` object.



```javascript

var a = list.push('A');

a.value(); //'A'

```



#### unshift(value)

Creates a node with the value specified, adds it to the beginning of the list and returns the `Node` object.



```javascript

var b = list.unshift('B');

b.value(); //'B'

```



### Accessing Nodes

#### pop

Returns the tail `Node` and removes it from the list.

```

var list = new List();

list.push('A');

list.push('B');



list.pop().value(); //'B'

```



#### shift

Returns the head `Node` and removes it from the list.

```

var list = new List();

list.push('A');

list.push('B');



list.shift().value(); //'A'

```



#### removeNode(node)

Remove a specific `Node` (An _O(1)_ complexity action in linked lists)

```

var list = new List();

list.push('A');

list.push('B');

list.push('C');

 

var node = list.find('B');

list.removeNode(node);

list.count(); // 2

list.get(0).value(); // 'A'

list.get(1).value(); // 'C';

```



#### get(index)

Returns the `Node` at the specified index. _(Linear Lookup, not very performant)_

```javascript

var list = new List();

list.push('A');

list.push('B');

list.push('C');



list.get(1).value(); //'B'

```



### Peeking

#### head()

Returns the head `Node` or `null` in list is empty

```javascript

var list = new List();

var node_a = list.push('A');

var node_b = list.push('B');



list.head() === node_a; // true

```



#### tail()

Returns the tail `Node` or `null` in list is empty

```javascript

var list = new List();

var node_a = list.push('A');

var node_b = list.push('B');



list.tail() === node_b; // true

```



### Searching

#### find(value)

Find the node with the specified value and returns it. _(Linear search, not very performant)_

```javascript

var list = new List();

list.push('A');

var node_b = list.push('B');



list.find('B') === node_b; // true

```



### Misc

#### set(index, value)

Sets the value of the `Node` at the specifiec index.

```javascript

var list = new List();

list.push('A');



list.set(0, 'B');

list.head().value(); // 'B'

```



#### count()

Returns the number of `Node`s in the list.

```javascript

var list = new List();

list.push('A');

list.push('B');



list.count(); // 2

```



#### isEmpty()

Returns `true` if list has no `Node`s and `false` if otherwise.

```javascript

var list = new List();

list.isEmpty(); // true



list.push('A');

list.isEmpty(); // false

```



#### truncateTo(length)

Truncates the list to the specified size.

```

var list = new List();

list.push('A');

list.push('B');



list.truncateTo(1);

list.count(); // 1

```



#### empty()

Same as calling `truncateTo(0)`. Empties the list.

```

var list = new List();

list.push('A');

list.push('B');



list.empty();



list.count();   // 0

list.isEmpty(); // true

```



### asArray()

Returns the list as an Array.

```javascript

var list = new List();

list.push('A');

list.push('B');



list.asArray(); // ['A', 'B']

```



## `Node` API

### Getters

#### value()

Returns the value of the `Node`



#### previous()

Returns the previous `Node` in the list of `null` if the node is the forst `Node`.



#### next()

Returns the next `Node` in the list of `null` if the node is the last `Node`.



### Setters

#### set(value)

Sets the value of the node

```

var node = new Node();

node.set('A');



node.value(); // 'A'

```



#### setPrevious(`Node` node)

Sets the previous pointer of the `Node`

```

var node_a = new Node();

var node_b = new Node();

node_b.setPrevious(node_a);



node_b.previous() === node_a; // true

```



#### setNext(`Node` node)

Sets the next pointer of the `Node`

```

var node_a = new Node();

var node_b = new Node();

node_a.setNext(node_b);



node_a.next() === node_b; // true

```



### Misc

#### isHead()

Retunrs true if the node is the first node in the list.

```javascript

var list = new List();

list.push('A');

list.push('B');



list.head().isHead(); // true

```



#### isTail()

Retunrs true if the node is the last node in the list.

```javascript

var list = new List();

list.push('A');

list.push('B');



list.tail().isTail(); // true

```



## Running Tests

```

npm test

```



if you have mocha installed, you may also run

```

mocha tests

```