liftjs

lift.js

Because it can always be shorter.

Introduction

lift.js is a compact monad opinionated javascript library. It implements Just, Maybe, Validation(Valid) and a nice Monad factory. The unit comes with a lift function so you can add functionnality later in code to your monad. It's ment to be flexible and faster to use. It's written with es6 so it's less than 100 lines.

Installation

lift.js can be required directly for es next project or you can use the lift-min.js for all legacy applications.

npm

npm install liftjs

lift (lifting)

  const justWithLog = Just(5).lift('log',console.log);
  justWithValue.log();
  // console> 5

All Monads

The folowing function are available on all monads.

bind, alias: chain flatMap

  bind(func, args)

  const justWithValue = Just(5).bind((value)=> Just(value));

  // Just[5]

of, alias: pure

  of(value)

  const justWithValue = Just(5).of(6);
  // Just[6]

  const justWithValue = Just(5).of(Just(6));
  // Just[6]

get

  get()

  const value = Just(5).get();
  //5

map

  map(func)

  const justWithValue = Just(7).map(value => value * 2);
  // Just[14]

join

  join()

  const justWithValue = Just(Just(5)).join()
  // Just[5]

toMaybe

  toMaybe()

  const maybeWithValue = Just(5).toMaybe();
  // Maybe[5]

run

  run(func)

  Just(5).run(value => console.log(value));
  // console> 5

Maybe

none, alias: nothing

  none()

  const maybeWithValue = Maybe().none()
  // Maybe[]

  const maybeWithValue = Maybe().nothing()
  // Maybe[]

  const maybeWithValue = Maybe()
  // Maybe[]

  const maybeWithValue = Maybe(undefined)
  // Maybe[]

  const maybeWithValue = Maybe(null)
  // Maybe[]

isNone, alias: isNothing

  isNone()

  const value = Maybe(5).isNone();
  // false

isJust, alias: orSome

  isJust()

  const value = Maybe(5).isJust();
  // true

orJust, alias: orSome

  orJust()

  const maybeWithValue = Maybe().orJust(15);
  // Maybe[15]

orElse

  orElse(monad)

  const maybeWithValue = Maybe(5).orElse(Maybe(15));
  // Maybe[5]

  const maybeWithValue = Maybe().orElse(Just(15));
  // Just[5]

Links

• npm
• @atomable
• @pre63

Author

Written and maintained by @pre63.

Sponsored by @atomable.

Based on Douglas Crockford MONAD. Special tanks to Monet for the inspiration and a bunch of tests.