fastseries

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Zero-overhead series function call for node.js.
Also supports each and map!

If you need zero-overhead parallel function call, check out
fastparallel.


Example for series call

``js
var series = require('fastseries')({
// if you want the results, then here you are
results: true
})

series(
{}, // what will be this in the functions
[something, something, something], // functions to call
42, // the first argument of the functions
done // the function to be called when the series ends
)

function late (arg, cb) {
console.log('finishing', arg)
cb(null, 'myresult-' + arg)
}

function something (arg, cb) {
setTimeout(late, 1000, arg, cb)
}

function done (err, results) {
console.log('series completed, results:', results)
}
`

Example for each and map calls

`js
var series = require('fastseries')({
// if you want the results, then here you are
// passing false disables map
results: true
})

series(
{}, // what will be this in the functions
something, // functions to call
[1, 2, 3], // the first argument of the functions
done // the function to be called when the series ends
)

function late (arg, cb) {
console.log('finishing', arg)
cb(null, 'myresult-' + arg)
}

function something (arg, cb) {
setTimeout(late, 1000, arg, cb)
}

function done (err, results) {
console.log('series completed, results:', results)
}
`

Caveats

The done function will be called only once, even if more than one error happen.

This library works by caching the latest used function, so that running a new series
does not cause any memory allocations.

Benchmarks

Benchmark for doing 3 calls setImmediate 1 million times:

`
benchSetImmediate*1000000: 2460.623ms
benchAsyncSeries*1000000: 3064.569ms
benchAsyncEachSeries*1000000: 2913.525ms
benchAsyncMapSeries*1000000: 3020.794ms
benchNeoSeries*1000000: 2617.064ms
benchNeoEachSeries*1000000: 2621.672ms
benchNeoMapSeries*1000000: 2611.294ms
benchTinyEachAsync*1000000: 2706.457ms
benchFastSeries*1000000: 2540.653ms
benchFastSeriesNoResults*1000000: 2538.674ms
benchFastSeriesEach*1000000: 2534.856ms
benchFastSeriesEachResults*1000000: 2545.394ms
``

Benchmarks taken on Node 12.16.1 on a dedicated server.

See bench.js for mode details.

License

ISC

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