hash-anything/README.md

Hash any Javascript primitive or object

# hash-anything
Hash (almost) any Javascript primitive or object.

### sha1(anything)
```javascript
var sha1 = require('hash-anything').sha1;

var hash1 = sha1({
    a: 1,
    b: 2
});
console.log(hash1); //a8fe01c7b160932d628ba94d8400b6615846e791

var hash2 = sha1(1234);
console.log(hash2); //9deba4ae0dab97a17b7e9c299af6e4d52d994f1a

var hash3 = sha1('some text');
console.log(hash3); //4d3dd7cdbb862bbe4b9d1470f74dc26c5262c016

var hash4 = sha1(56.78);
console.log(hash4); //ac8433e96f689a49f3d54a52bb07d6e697dfc2ab
```

### md5(anything)
```javascript
var md5 = require('hash-anything').md5;

var hash = md5({
    a: 1,
    b: 2
});

console.log(hash); //f8761944960a318b27a1ee4104351f8a
```

### sha256(anything)
```javascript
var sha256 = require('hash-anything').sha256;

var hash = sha256({
    a: 1,
    b: 2
});

console.log(hash); //3c6d145329ac03391eb3db110935dbbc9e006af8c9da674f0c01b2c0e04f1fa6
```

### sha512(anything)
```javascript
var sha512 = require('hash-anything').sha512;

var hash = sha512({
    a: 1,
    b: 2
});

console.log(hash); //4f54bacd20498e42ca5c0f1c275032eb47b740e1a81db5af835d6310fc6b92ff678d09a9cb15c12e3f8780886c91c8ea242bd28de60618af8dd9b70620746fb6
```

### new Hash(algorithm) - Hash multiple things at once.
algorithm (string) = 'sha1', 'md5', 'sha256', or 'sha512'

* **hash(anything)** - add anything to the hash calculation
* **getValue()** - get the hash value of everything added to the Hash object
* **clear()** - clears the contents of the Hash object, so it can be reused.

```javascript
var Hash = require('hash-anything').Hash;

var hash = new Hash('sha1')
    .hash(1234)
    .hash('some text')
    .hash(new Date(2013, 1, 1))
    .hash(567.89)
    .hash(/regex/);

console.log(hash.getValue()); //2e3518275983ee7ad81cc9a68fdc634ea9777dfc
```

### new Hash(function) - Use a custom hashing routine.
The routine should take a Buffer and return the hash.

This example uses the [xxhash module](https://github.com/mscdex/node-xxhash). It implements [xxHash](https://github.com/Cyan4973/xxHash). xxHash is a fast, non-cryptographic hash algorithm. Do not use it for security, but it's great for comparing, caching, indexing, etc.
```javascript
var Hash = require('hash-anything').Hash;
var XXHash = require('xxhash');

var doHash = function(buf) {
    var hasher = new XXHash(0x6d4e9ec6); //random seed
    hasher.update(buf);
    return hasher.digest();
};

var hash = new Hash(doHash)
    .hash(1234)
    .hash('some text')
    .hash(new Date(2013, 1, 1))
    .hash(567.89)
    .hash(/regex/);

console.log(hash.getValue()); //3804156080
```

### Supported Types ###
* Primatives: Boolean, Number, String, BigInt, undefined, and Symbol
* Built-In Objects: Date, RegExp, Null, Object, Function, TypedArrays(Uint16Array, etc.), Map, Set,
GeneratorFunction, AsyncFunction
* Global Properties: Nan, Infinity

### Unsupported Types ###
* WeakMap
* WeakSet
* Promise
* DataView

### Circular References ###
Currently, `hash-anything` does not support circular references. They will cause a stack overflow error. 

### Note on New Types ###
When a new built-in type is added to Javascript, `hash-anything` usually needs be updated to support it. Otherwise, the new type will be treated like any other user-defined objects. This may not produce ideal results..