# yallist

Yet Another Linked List

There are many doubly-linked list implementations like it, but this
one is mine.

For when an array would be too big, and a Map can't be iterated in
reverse order.


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## basic usage

```javascript
var yallist = require('yallist')
var myList = yallist.create([1, 2, 3])
myList.push('foo')
myList.unshift('bar')
// of course pop() and shift() are there, too
console.log(myList.toArray()) // ['bar', 1, 2, 3, 'foo']
myList.forEach(function (k) {
  // walk the list head to tail
})
myList.forEachReverse(function (k, index, list) {
  // walk the list tail to head
})
var myDoubledList = myList.map(function (k) {
  return k + k
})
// now myDoubledList contains ['barbar', 2, 4, 6, 'foofoo']
// mapReverse is also a thing
var myDoubledListReverse = myList.mapReverse(function (k) {
  return k + k
}) // ['foofoo', 6, 4, 2, 'barbar']

var reduced = myList.reduce(function (set, entry) {
  set += entry
  return set
}, 'start')
console.log(reduced) // 'startfoo123bar'
```

## api

The whole API is considered "public".

Functions with the same name as an Array method work more or less the
same way.

There's reverse versions of most things because that's the point.

### Yallist

Default export, the class that holds and manages a list.

Call it with either a forEach-able (like an array) or a set of
arguments, to initialize the list.

The Array-ish methods all act like you'd expect.  No magic length,
though, so if you change that it won't automatically prune or add
empty spots.

### Yallist.create(..)

Alias for Yallist function.  Some people like factories.

#### yallist.head

The first node in the list

#### yallist.tail

The last node in the list

#### yallist.length

The number of nodes in the list.  (Change this at your peril.  It is
not magic like Array length.)

#### yallist.toArray()

Convert the list to an array.

#### yallist.forEach(fn, [thisp])

Call a function on each item in the list.

#### yallist.forEachReverse(fn, [thisp])

Call a function on each item in the list, in reverse order.

#### yallist.get(n)

Get the data at position `n` in the list.  If you use this a lot,
probably better off just using an Array.

#### yallist.getReverse(n)

Get the data at position `n`, counting from the tail.

#### yallist.map(fn, thisp)

Create a new Yallist with t