Galago NPM | npm.io

galago

galago /ɡəˈleɪɡoʊz/ is a set of very specific, opinionated helper functions for functional-like programming in js. It’s also the name of this animal.

🚧 Work in progress, but feel free to:

yarn add galago
# or
npm install galago --save

Or grab the source from src/index.js or lib/index.js (ES2015) and pluck it into your codebase as vendor code. The world is your oyster. ¯\_(ツ)_/¯

`compose` and `composeAsync`

Both of these functions recursively reduce an a array of functions by being a typical compose function / pipe mechanism. You can terminate the mechanism early by suppyling a reduced? function which check the output at each step.

Both functions accept the same three parameters:

`@param {*} — used to provide the initial value
@param {array<Function>} fns — array of function to execute
@param {?function} reducedFn — optional function with signature fn(x: Any): Boolean; if returning true, exits the call and returns the last result

compose returns {*} (whatever you want), while composeAsync returns a {Promise}.

Important note: the functions supplied to composeAsync don’t all have to be async/Promises — you can mix and match!

Usage example for compose

const transducer = (data) =>
  compose(
    data,
    [fn1, fn2, fn3, fn4, … fnX]
  );

Full explenation and code here.

You can also clone the repo and run yarn run example:transducer to run this sample code.

Usage example for composeAsync

const fakeHttpEndpoint = (requestBody) =>
  composeAsync(
    requestBody, // acc param
    [ // list of functions
      parse,
      validate,
      transform,
      saveToDb,
    ],
    isReduced // reducedFn param
  );

Full explenation and code here.

You can also clone the repo and run yarn run example:fakeHttp to run this sample code.