pipe-functions

    1.3.0 • Public • Published

    pipe-functions

    Build Status

    Pipe functions in a Unix-like style. It supports Promises (async) anywhere in the pipeline and every step will be executed sequentially. The return (resolve in case of Promises) of each function will be passed in as an argument to the next one

    Key features:

    • Supports Promises, or any lib following the Promises/A+ spec about being thenable (.then() method)
    • Promises will be executed sequentially
    • First argument can be of any type (String, Number, Date, etc.) or even a Function or a Promise
    • Node.js and Browser ready (to be used on a Browser, without a build step, check lib/pipe-non-es6.js)
    • Lightweight, 501 bytes, before gzip!

    Install

    NPM / Node

    npm install pipe-functions

    Usage

    Sync

    const pipe = require('pipe-functions');
     
    // First argument can be of any type
    const result = pipe('input', fn1, fn2, fnN);
    // And also a function
    const result2 = pipe(fn0, fn1, fn2, fnN);

    Async (Promises)

    If the pipeline contains a Promise anywhere in the pipeline, we must treat pipe like a Promise itself, so we must to use .then() to get the final result.

    const pipe = require('pipe-functions');
     
    // First argument can be of any type, as shown in the previous example
    pipe('input', fn1, fnPromise1, fn2, fnPromise2).then(console.log);

    A suggestion regarding Promises. Probably you've seen, or had to write, a stack of promises like that:

    someAsyncFunction('param')
      .then(doSomethingWithTheResult)
      .then(doSomethingElseWithTheResultOfTheLast)
      .then(oneMore)
      .then(almostThere)
      .then(done)
      .catch(console.log)

    It could be written as:

    const pipe = require('pipe-functions');
     
    pipe(
        someAsyncFunction('param'),
        doSomethingWithTheResult,
        doSomethingElseWithTheResultOfTheLast,
        oneMore,
        almostThere,
        done
    ).catch(console.log)

    Examples

    OBS: Some examples needs a platform with support for Destructuring (Nodejs v6+, Chrome).

    Sync

    const pipe = require('pipe-functions');
     
    /** Functions **/
    const capitalize = v => v[0].toUpperCase() + v.slice(1);
    const quote = v => `"${v}"`;
     
    /** Pipe **/
    // result will be: "Time"
    const result = pipe('time', capitalize, quote);

    Async (Promises)

    const pipe = require('pipe-functions');
     
    /** Functions **/
    // Sync
    const capitalize = v => v[0].toUpperCase() + v.slice(1);
    // Async
    const fetchAndSetBandName = v => new Promise((resolve, reject) => setTimeout(() => resolve(`Pink Floyd - ${v}`), 1000));
     
    /** Pipe **/
    // the result will be: Pink Floyd - Time
    pipe('time', capitalize, fetchAndSetBandName).then(console.log)

    Example with destructuring,

    To easily pass in more than one value (within an Object or Array) through the pipeline.

    const pipe = require('pipe-functions');
     
    /** Functions **/
    // Async
    const fetchBandName = ({ song }) => new Promise((resolve, reject) =>
    setTimeout(() => resolve({ song, band: 'Pink Floyd' }), 1000));
    // Sync
    const concatBandAndSong = ({ song, band }) => `${band} - ${song}`;
     
    /** Pipe **/
    // the result will be: Pink Floyd - Time
    pipe('time', fetchBandName, concatBandAndSong).then(console.log)

    Install

    npm i pipe-functions

    DownloadsWeekly Downloads

    26,279

    Version

    1.3.0

    License

    MIT

    Last publish

    Collaborators

    • avatar