hat
===

Generate random IDs and avoid collisions.

![hat](http://substack.net/images/hat.png)

examples
========

hat
---

````javascript
var hat = require('hat');

var id = hat();
console.log(id);
````

output:

````
0c82a54f22f775a3ed8b97b2dea74036
````

rack
----

````javascript
var hat = require('hat');
var rack = hat.rack();

console.log(rack());
console.log(rack());
````

output:

````
1c24171393dc5de04ffcb21f1182ab28
fabe2323acc1b559dee43d4a1e16cbeb
````

methods
=======

var hat = require('hat');

hat(bits=128, base=16)
----------------------

Generate a random ID string with `bits` of data in a `base`.

Leading zeros are appended such that all outputs for a given number of bits have
equal length.

var rack = hat.rack(bits=128, base=16, expandBy)
------------------------------------------------

Make a new hat rack. Call `rack()` repeatedly to generate new IDs which are
checked for collisions.

If `expandBy` is specified, increment `bits` by this amount if too many
collisions occur. If `expandBy` isn't specified, `rack()` will throw if too many
collisions occur during generation.

Optionally call `var id = rack(data)` to store `data` at the new ID.

You can get the data out again with `rack.get(id)` and set the data with
`rack.set(id, value)`.