Getting Started

Installation

crocks is available from npm and is just a shell command away. All you need to do is run the following to save it as a dependency in your current project folder:

$ npm install crocks -S

This will pull down crocks into your project's node_modules folder and can be accessed by adding something like the following in the file that needs it:

// node require syntax

const crocks = require('crocks')

// JavaScript modules (if you are transpiling)

import crocks from 'crocks'

Import only what's needed

There is a lot to this library, and as such it may not be desired to bring in the whole thing when bundling for a library or frontend application. If this is the case, the code is organized in a manner that groups all functions that return or construct a given ADT into their respective folders. While general purpose functions are spread across the following folders: combinators, helpers, logic, pointfree and predicates.

To access the types, just reference the folder like: crocks/Maybe, or crocks/Result. If you want to access a function that constructs a given type, reference it by name, like: crocks/Maybe/safe or crocks/Result/tryCatch. This organization helps ensure that you only include what you need.

Entire library (CommonJS)

Source

Runkit

// namespace entire suite to crocks variable

const crocks = require('crocks')

// pluck anything that does not require name-spacing

const { safe, isNumber } = crocks

// still requires entire object, but removes name-spacing

const { and, liftA2 } = require('crocks')

// divide :: Number -> Number

const divide =

x => y => x / y

// safeNumber :: a -> Maybe Number

const safeNumber =

safe(isNumber)

// notZero :: a -> Maybe Number

const notZero = safe(

and(isNumber, x => x !== 0)

)

// safeDivide:: a -> Maybe Number

const safeDivide = crocks.curry(

(x, y) => liftA2(divide, safeNumber(x), notZero(y))

)

safeDivide(20, 0)

//=> Nothing

safeDivide(20, 5)

//=> Just 4

safeDivide('number', 5)

//=> Nothing

Entire library (JS Modules)

Source

Runkit

// namespace entire suite to crocks variable

import crocks from 'crocks'

// still imports entire object, but removes name-spacing

import { and, liftA2 } from 'crocks'

// pluck anything that does not require name-spacing

const { safe, isNumber } = crocks

// divide :: Number -> Number

const divide =

x => y => x / y

// safeNumber :: a -> Maybe Number

const safeNumber =

safe(isNumber)

// notZero :: a -> Maybe Number

const notZero = safe(

and(isNumber, x => x !== 0)

)

// safeDivide:: a -> Maybe Number

const safeDivide = crocks.curry(

(x, y) => liftA2(divide, safeNumber(x), notZero(y))

)

safeDivide(20, 0)

//=> Nothing

safeDivide(20, 5)

//=> Just 4

safeDivide('number', 5)

//=> Nothing

Single entities (CommonJS)

Source

Runkit

// require in each entity directly

const and = require('crocks/logic/and')

const curry = require('crocks/helpers/curry')

const isNumber = require('crocks/predicates/isNumber')

const liftA2 = require('crocks/helpers/liftA2')

const safe = require('crocks/Maybe/safe')

// divide :: Number -> Number

const divide =

x => y => x / y

// safeNumber :: a -> Maybe Number

const safeNumber =

safe(isNumber)

// notZero :: a -> Maybe Number

const notZero = safe(

and(isNumber, x => x !== 0)

)

// safeDivide:: a -> Maybe Number

const safeDivide = curry(

(x, y) => liftA2(divide, safeNumber(x), notZero(y))

)

safeDivide(20, 0)

//=> Nothing

safeDivide(20, 5)

//=> Just 4

safeDivide('number', 5)

//=> Nothing

Single entities (JS Modules)

Source

Runkit

// import in each entity directly

import and from 'crocks/logic/and'

import curry from 'crocks/helpers/curry'

import isNumber from 'crocks/predicates/isNumber'

import liftA2 from 'crocks/helpers/liftA2'

import safe from 'crocks/Maybe/safe'

// divide :: Number -> Number

const divide =

x => y => x / y

// safeNumber :: a -> Maybe Number

const safeNumber =

safe(isNumber)

// notZero :: a -> Maybe Number

const notZero = safe(

and(isNumber, x => x !== 0)

)

// safeDivide:: a -> Maybe Number

const safeDivide = curry(

(x, y) => liftA2(divide, safeNumber(x), notZero(y))

)

safeDivide(20, 0)

//=> Nothing

safeDivide(20, 5)

//=> Just 4

safeDivide('number', 5)

//=> Nothing