fandy 👋

A set of JavaScript utility functions I find myself needing frequently.

None of these are functions you can't find elsewhere, but I often find myself needing some of these, and not wanting to add a large dependency like lodash to my project.

This project is also a chance for me to practice setting up CI, full test coverage and a real README for the first time.

Feel free to make pull requests.

Install

npm install fandy --save

Install dependencies

npm install

Run tests

npm test

Functions

pipe(...fns)

Returns a function which returns the result of its arguments being passed one by one through fns

const first = x => x + 1
const second = x => x * 2

const result = pipe(first, second)(1)

// result = 4

split(string, token)

Returns an array consisting of string split on token

const string = 'I-am-a-string'
const result = split(string, '-')

// result = ['I', 'am', 'a', 'string']

uniq(array)

Returns a new array consisting of array with all duplicates removed.

const array = ['Bob', 'James', 'Bob']
const result = uniq(array)

// result = ['Bob', 'James']

zip(keys, ...arrays)

Returns an array objects created by zipping each array with keys

const firstNames = ['Bob', 'James', 'Tim']
const lastNames = ['Builder', 'Rocket', 'Tiny']
const cities = ['London', 'Paris']
const keys = ['firstName', 'lastName', 'currentCity']
const result = zip(keys, firstNames, lastNames, cities)

// result = [
//    { firstName: 'Bob', lastName: 'Builder', currentCity: 'London' },
//    { firstName: 'James', lastName: 'Rocket', currentCity: 'Paris' },
//    { firstName: 'Tim', lastName: 'Tiny', currentCity: undefined }
//  ]

last(array, index = 1)

Returns the index-th item from the end of array

const array = ['Bob', 'James', 'Robert']
const result = last(array)
// result = 'Robert'

const array = ['Bob', 'James', 'Robert']
const result = last(array, 2)
// result = 'James'

removeAt(array, index)

Returns a new array consisting of array with element at index removed

const array = ['Bob', 'James', 'Robert']
const result = removeAt(array, 1)
// result = ['Bob', 'Robert']

switcher(cases, otherwise, value)

Returns the case which has a key that matches value. If none match, returns otherwise

const cases = {
  true: "It's true",
  false: "It's false"
}
const result = switcher(cases, 'otherwise', true)
// result = "It's true"

const cases = {
  'test': "It's a test",
  'other': "It's something else"
}
const result = switcher(cases, 'otherwise', 'other')
// result = "It's something else"

const cases = {
  true: "It's true",
  false: "It's false"
}
const result = switcher(cases, 'otherwise', 'none of the above')
// result = 'otherwise'

const cases = {
  true: () => "It's true",
  false: "It's false"
}
const result = switcher(cases, 'default', true)
// result = "It's true"