fastfall

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call your callbacks in a waterfall, without overhead

Benchmark for doing 3 calls setImmediate 100 thousands times:

* non-reusable setImmediate: 407ms
* async.waterfall: 1203ms
* run-waterfall: 1432ms
* insync.wasterfall:
1570ms
* neo-async.wasterfall:
445ms
* waterfallize: 757ms
* fastfall: 432ms
* fastfall compiled: 428ms

These benchmarks where taken via bench.js on node 4.2.2, on a MacBook
Pro Retina 2014 (i7, 16GB of RAM).

If you need zero-overhead series function call, check out
fastseries, for parallel calls check out
fastparallel, and for a fast work queue
use fastq.


Install

``
npm install fastfall --save
`

Usage

`js
var fall = require('fastfall')()

fall([
function a (cb) {
console.log('called a')
cb(null, 'a')
},
function b (a, cb) {
console.log('called b with:', a)
cb(null, 'a', 'b')
},
function c (a, b, cb) {
console.log('called c with:', a, b)
cb(null, 'a', 'b', 'c')
}], function result (err, a, b, c) {
console.log('result arguments', arguments)
})
`

You can also set this when you create a fall:

`js
var that = { hello: 'world' }
var fall = require('fastfall')(that)

fall([a, b, c], result)

function a (cb) {
console.log(this)
console.log('called a')
cb(null, 'a')
}

function b (a, cb) {
console.log('called b with:', a)
cb(null, 'a', 'b')
}

function c (a, b, cb) {
console.log('called c with:', a, b)
cb(null, 'a', 'b', 'c')
}

function result (err, a, b, c) {
console.log('result arguments', arguments)
}
`

You can also set this when you run a task:

`js
var that = { hello: 'world' }
var fall = require('fastfall')()

fall(new State('world'), [
a, b, c,
], console.log)

function State (value) {
this.value = value
}

function a (cb) {
console.log(this.value)
console.log('called a')
cb(null, 'a')
}

function b (a, cb) {
console.log('called b with:', a)
cb(null, 'a', 'b')
}

function c (a, b, cb) {
console.log('called c with:', a, b)
cb(null, 'a', 'b', 'c')
}
`

$3

`js
var fall = require('fastfall')([
function a (arg, cb) {
console.log('called a')
cb(null, arg)
},
function b (a, cb) {
console.log('called b with:', a)
cb(null, 'a', 'b')
},
function c (a, b, cb) {
console.log('called c with:', a, b)
cb(null, 'a', 'b', 'c')
}])

// a compiled fall supports arguments too!
fall(42, function result (err, a, b, c) {
console.log('result arguments', arguments)
})
`

You can set this by doing:

`js
var that = { hello: 'world' }
var fall = require('fastfall')(that, [
function a (arg, cb) {
console.log('this is', this)
console.log('called a')
cb(null, arg)
},
function b (a, cb) {
console.log('called b with:', a)
cb(null, 'a', 'b')
},
function c (a, b, cb) {
console.log('called c with:', a, b)
cb(null, 'a', 'b', 'c')
}])

// a compiled fall supports arguments too!
fall(42, function result (err, a, b, c) {
console.log('result arguments', arguments)
})
`

or you can simply attach it to an object:

`js
var that = { hello: 'world' }
that.doSomething = require('fastfall')([
function a (arg, cb) {
console.log('this is', this)
console.log('called a')
cb(null, arg)
},
function b (a, cb) {
console.log('called b with:', a)
cb(null, 'a', 'b')
},
function c (a, b, cb) {
console.log('called c with:', a, b)
cb(null, 'a', 'b', 'c')
}])

// a compiled fall supports arguments too!
that.doSomething(42, function result (err, a, b, c) {
console.log('this is', this)
console.log('result arguments', arguments)
})
`

API

$3

Creates a fall, it can either be pre-filled with a this value
and an array of functions.

If there is no list of functions, a not-compiled fall
is returned, if there is a list of function a compiled fall
is returned.

$3

Calls the functions in a waterfall, forwarding the arguments from one to
another. Calls done when it has finished.

$3

Calls the compiled functions in a waterfall, forwarding the arguments from one to
another. Additionally, a user can specify some arguments for the first
function, too. Calls done` when it has finished.

License

MIT

[npm-badge]: https://badge.fury.io/js/fastfall.svg
[npm-url]: https://badge.fury.io/js/fastfall
[travis-badge]: https://api.travis-ci.org/mcollina/fastfall.svg
[travis-url]: https://travis-ci.org/mcollina/fastfall
[coveralls-badge]:https://coveralls.io/repos/mcollina/fastfall/badge.svg?branch=master&service=github
[coveralls-url]: https://coveralls.io/github/mcollina/fastfall?branch=master
[david-badge]: https://david-dm.org/mcollina/fastfall.svg
[david-url]: https://david-dm.org/mcollina/fastfall