christophwitzko/parallizer

# Parallizer
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> Parallizer is a tool that makes working with asynchronous functions much easier.

## Installation

    $ npm install parallizer --save

## Example

```js
var Parallizer = require('parallizer')

// creates a new Parallizer object
// that will only run 3 functions at the same time.
var prl = new Parallizer(3)

// very important: last argument must be the callback.
var add2 = function (id, rnd, cb) {
  setTimeout(cb.bind(null, id, rnd), 100)
}

for (var i = 0; i < 100; i++) {
  var rnd = Math.floor(Math.random()  *500)
  prl.sadd(add2, 'ID#' + i, rnd, function (id, rnd) {
    console.log(id + ': ' + rnd)
  })
}

```

## Documentation

### new Parallizer([max], [cb], [paused])

Creates an new Parallizer object.

**Arguments**

* `max` - The maximum concurrent running functions. (Default: 1)
* `cb` - The callback that will be called if all functions have been executed.
* `paused` - The queue is initially paused.

---------------------

### parallizer.sadd(fn[, arg1[, arg2[, ...]]])

Adds a function to the queue an executes it if possible.

**Arguments**

* `fn` - The function to be called, last argument must be a callback.
* `arg1, arg2, ...` - Arguments for `fn`.

---------------------

### parallizer.add(fn, [args], [cb], [scope], [high])

This function does the same like `parallizer.sadd`, but with a different API.

**Arguments**

* `fn` - The function to be called, last argument must be a callback.
* `args` - An array specifying the arguments with which `fn` should be called.
* `cb` - Callback (last argument) of `fn`.
* `scope` - The scope (this reference) in which the `fn` is executed.
* `high` - If `true`, pushes `fn` in front of the queue.

---------------------

### parallizer.start()

Starts the paused queue.

---------------------

### parallizer.pause()

Pauses the queue.

## Tests

    $ npm install && npm test

## Licence

The [MIT License (MIT)](http://opensource.org/licenses/MIT)

Copyright © 2015 [Christoph Witzko](https://twitter.com/christophwitzko)