js-toolbox

Useful JavaScript utilities (with TypeScript typings).

$ npm i @xcmats/js-toolbox

Works in node.js and browser environments (use webpack or Rollup to bundle it with your project).

index

• documentation
• play in your browser
• use the package
  • install
  • play in node.js
  • example use in ES6 modules code
• use the source
• namespaces
  • array
  • async
  • codec
  • func
  • math
  • memory
  • redux
  • string
  • struct
  • type
  • utils
• examples
  • array manipulation
  • asynchronous programming
  • base64 encoding and decoding
  • hex encoding and decoding
  • byte array manipulation
  • functional programming
  • simple math
  • shared memory pattern
  • operating on strings
  • data structure manipulation
  • type primitives
• notes
• license

documentation

API Reference

play in your browser

RunKit with @xcmats/js-toolbox

• list member functions (link):

  var jsToolbox = require("@xcmats/js-toolbox")
  
  Object.keys(jsToolbox).sort()

  [ "Y",
    "access",
    "actionCreators",
    "add",
    "app",
    "array",
    "arrayDifference",
    "arrayIntersection",
    "arrayIsSubset",
    "arraySetEqual",
    "asciiLetters",
    "asciiLowercase",
    "asciiUppercase",
    "async",
    "asyncMap",
    "asyncRace",
    "asyncReduce",
    "asyncRepeat",
    "average",
    "b64ToHex",
    ... ]

• play with shuffle and range (link):

  jsToolbox.shuffle(jsToolbox.range(16))

  [ 14, 12, 15, 8, 13, 4, 5, 6, 1, 7, 10, 0, 2, 3, 9, 11 ]

• do all other things shown in examples section below

use the package

install

$ mkdir playground
$ cd playground/
$ npm init
...
$ npm i @xcmats/js-toolbox
...

play in node.js

$ node
>

t = require("@xcmats/js-toolbox")

{ ...
array:
 { ... },
...
utils:
 { ... } }

example use in ES6 modules code

import { range } from "@xcmats/js-toolbox/array"
import { stringToB64 } from "@xcmats/js-toolbox/codec"
import { flow } from "@xcmats/js-toolbox/func"
import { random } from "@xcmats/js-toolbox/string"

const b64stringify = flow(
    JSON.stringify,
    stringToB64
)

let spam = b64stringify({
    tenNumbers: range(10),
    randomLetters: random(20)
})

console.log("Stringified and b64-encoded object: ", spam)

use the source

$ git clone git@github.com:drmats/js-toolbox.git
Cloning into 'js-toolbox'...
$ cd js-toolbox
$ npm i
$ npm start
Compiling for 'commonjs' ...
🎉  Successfully compiled 11 files with Babel.
>

namespaces

If you're experimenting via RunKit then prepend all namespaces with "jsToolbox." and if you're experimenting inside node.js console with npm package (as described above) then prepend all namespaces with "t.". If you're using the source and have launched node.js session via npm start then you're good to go ( ¯\_(ツ)_/¯ ).

array utilities

array

{ append: [Function: append],
  countBy: [Function: countBy],
  difference: [Function: difference],
  draw: [Function: draw],
  drop: [Function: drop],
  dropLast: [Function: dropLast],
  findDuplicates: [Function: findDuplicates],
  flatten: [Function: flatten],
  head: [Function: head],
  init: [Function: init],
  intersection: [Function: intersection],
  isContinuous: [Function: isContinuous],
  isSorted: [Function: isSorted],
  isSubset: [Function: isSubset],
  last: [Function: last],
  range: [Function: range],
  removeDuplicates: [Function],
  setEqual: [Function: setEqual],
  shuffle: [Function: shuffle],
  sparse: [Function: sparse],
  tail: [Function: tail],
  take: [Function: take],
  takeEvery: [Function: takeEvery],
  takeLast: [Function: takeLast],
  zipWith: [Function: zipWith],
  zip: [Function] }

asynchronous programming helpers

async

{ cancellable: [Function: cancellable],
  createMutex: [Function: createMutex],
  delay: [Function: delay],
  interval: [Function: interval],
  map: [Function: map],
  parMap: [Function: parMap],
  race: [Function: race],
  reduce: [Function: reduce],
  repeat: [Function: repeat],
  timeout: [Function: timeout] }

TypedArray coders/decoders

codec

{ concatBytes: [Function: concatBytes],
  compareBytes: [Function: compareBytes],
  stringToBytes: [Function],
  bytesToString: [Function],
  hexToBytes: [Function: hexToBytes],
  bytesToHex: [Function: bytesToHex],
  b64dec: [Function],
  b64enc: [Function],
  b64ToString: [Function],
  stringToB64: [Function],
  b64ToHex: [Function],
  hexToB64: [Function],
  random: [AsyncFunction],
  timestamp: [Function: timestamp] }

functional programming tools

func

{ app: [Function: app],
  choose: [Function: choose],
  compose: [Function: compose],
  curry: [Function: curry],
  curryN: [Function: curryN],
  curryThunk: [Function: curryThunk],
  flow: [Function: flow],
  handleException: [Function: handleException],
  identity: [Function: identity],
  lazyish: [Function: lazyish],
  locker: [Function: locker],
  local: [Function: local],
  partial: [Function: partial],
  pipe: [Function: pipe],
  rearg: [Function: rearg],
  Y: [Function: Y] }

basic math

math

{ add: [Function],
  average: [Function: average],
  clamp: [Function: clamp],
  dec: [Function],
  div: [Function],
  inc: [Function],
  inv: [Function],
  log10: [Function: log10],
  log2: [Function: log2],
  mod: [Function],
  mul: [Function],
  neg: [Function],
  pow: [Function],
  product: [Function: product],
  randomInt: [Function: randomInt],
  roundIfClose: [Function: roundIfClose],
  sub: [Function],
  sum: [Function: sum] }

shared memory

memory

{ useMemory: [Function: useMemory],
  share: [Function: share] }

some goodies for redux

redux

{ actionCreators: [Function: identity],
  createReducer: [Function: createReducer] }

string utilities

string

{ asciiLetters: [Function: asciiLetters],
  asciiLowercase: [Function: asciiLowercase],
  asciiUppercase: [Function: asciiUppercase],
  big: [Function],
  camelToPascal: [Function: camelToPascal],
  camelToSnake: [Function: camelToSnake],
  capitalize: [Function: capitalize],
  digits: [Function: digits],
  ellipsis: { [Function: ellipsis] BEGIN: 0, MIDDLE: 1, END: 2 },
  empty: [Function: empty],
  space: [Function: space],
  nl: [Function: nl],
  tab: [Function: tab],
  padLeft: [Function: padLeft],
  padRight: [Function: padRight],
  pascalToCamel: [Function: pascalToCamel],
  pascalToSnake: [Function: pascalToSnake],
  quote: [Function: quote],
  random: [Function: random],
  shorten: { [Function: shorten] BEGIN: 0, MIDDLE: 1, END: 2 },
  snakeToCamel: [Function: snakeToCamel],
  snakeToPascal: [Function: snakeToPascal],
  wrap: [Function: wrap] }

data structure manipulation tools

struct

{ access: [Function: access],
  clone: [Function],
  hashAccessor: [Function: hashAccessor],
  keyAccessor: [Function: keyAccessor],
  dfs: [Function: dfs],
  dict: [Function: dict],
  objectMap: [Function: objectMap],
  objectReduce: [Function: objectReduce],
  swap: [Function: swap] }

type helpers

type

{ isArray: [Function: isArray],
  isFunction: [Function: isFunction],
  isNumber: [Function: isNumber],
  isObject: [Function: isObject],
  isString: [Function: isString],
  maxInt: 9007199254740991,
  minInt: -9007199254740991,
  nullToUndefined: [Function: nullToUndefined],
  toBool: [Function: toBool] }

uncategorized utilities

utils

{ devEnv: [Function: devEnv],
  getLibConfig: [Function: getLibConfig],
  getProcess: [Function: getProcess],
  isBrowser: [Function: isBrowser],
  rgb: [Function: rgb],
  rgba: [Function: rgba],
  run: [Function: run],
  timeUnit: { ... },
  to_: [Function: to_],
  url: [Function: url] }

examples

array manipulation

• Find the lenghts of the words in a given sentence and count how many of them exists in each length group.

  array.countBy(
      'exemplo plus quam ratione vivimus'.split(' '),
      w => w.length
  )

  { '4': 2, '7': 3 }

• Choose a random element from a given array (or a random character from a given string).

  array.draw(string.asciiLetters())

  'S'

• Find duplicates in a given array.

  array.findDuplicates(['one', 'two', 'one', 'six', 'two', 'two'])

  [ 'one', 'two' ]

• Flatten passed array, i.e. transform [[1, 2,], ..., [3, 4,],] to [1, 2, ..., 3, 4,].

  array.flatten(Object.entries({ a: 'b', c: 'd', e: 'f' }))

  [ 'a', 'b', 'c', 'd', 'e', 'f' ]

• Return a list containing an arithmetic progression. range(i, j) returns [i, i+1, i+2, ..., j-1]. Possible invocations are: range(stop), range(start, stop), range(start, stop, step). When start is omitted it defaults to 0. When step is given, it specifies the increment (or decrement).

  array.range(10)

  [ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 ]

  array.range(-128, -256, -16)

  [ -128, -144, -160, -176, -192, -208, -224, -240 ]

• Randomly shuffle all elements in the given array (Durstenfeld's modification to the Fisher-Yates shuffle algorithm). The operation is taken in-place.

  array.shuffle(array.range(12))

  [ 9, 7, 0, 8, 2, 10, 3, 1, 11, 4, 5, 6 ]

• Generate sparse array of distinct integers. sparse(stop, size) returns array of size distinct integers in range [0..stop-1]. sparse(start, stop, size) returns array of size distinct integers in range [start..stop-1].

  array.sparse(1024, 8)

  [ 6, 34, 170, 422, 530, 643, 855, 862 ]

• "Zip" given arrays using provided f operator.

  array.zipWith((a, b) => a + b) ([1, 2, 3, 4], [10, 20, 30, 40])

  [ 11, 22, 33, 44 ]

• Take every 3rd element from a given array.

  array.takeEvery(3) ([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])

  [0, 3, 6, 9]

asynchronous programming

• Delay current async execution by time miliseconds.

  (async () => {
      await async.delay()
      console.log('Hello ...')
      await async.delay()
      console.log('... world')
  }) ()

  Promise { <pending> }
  Hello ...
  ... world

• Invoke a sequence of asynchronous operations on an array of elements.

  (async () => {
      let x = await async.map(
          array.range(10),
          x => async.timeout(() => {
              console.log(4*x);
              return 4*x;
          }, array.head(array.sparse(1000, 1)))
      )
      console.log(`Result: ${x}`)
  }) ()

  Promise { <pending> }
  0
  4
  8
  12
  16
  20
  24
  28
  32
  36
  Result: 0,4,8,12,16,20,24,28,32,36

• Paralelly execute operation on each element of the array.

  (async () => {
      let x = await async.parMap(
          array.range(10),
          x => async.timeout(() => {
              console.log(4*x);
              return 4*x;
          }, array.head(array.sparse(1000, 1)))
      )
      console.log(`Result: ${x}`)
  }) ()

  Promise { <pending> }
  24
  8
  16
  12
  28
  20
  0
  36
  32
  4
  Result: 0,4,8,12,16,20,24,28,32,36

• Accumulate value over an array of elements using asynchronous operation.

  (async () => {
      let x = await async.reduce(
          array.range(10),
          (acc, x) => async.timeout(() => {
              console.log(acc+x);
              return acc+x;
          }, 100*x)
      )
      console.log(`Accumulated value: ${x}`)
  }) ()

  Promise { <pending> }
  0
  1
  3
  6
  10
  15
  21
  28
  36
  45
  Accumulated value: 45

base64 encoding and decoding

• Convert UTF-8 string into an array of bytes.

  codec.stringToBytes('Koń: 🐎')

  Uint8Array [ 75, 111, 197, 132, 58, 32, 240, 159, 144, 142 ]

• Convert array of bytes into a UTF-8 string.

  data = Uint8Array.from([70, 111, 120, 58, 32, 240, 159, 166, 138])

  Uint8Array [ 70, 111, 120, 58, 32, 240, 159, 166, 138 ]

  codec.bytesToString(data)

  'Fox: 🦊'

• Encode given byte array to Base64. Base64 encoding in browser and node.js.

  data = Uint8Array.from([240, 159, 142, 169, 240, 159, 144, 176])

  Uint8Array [ 240, 159, 142, 169, 240, 159, 144, 176 ]

  codec.b64enc(data)

  '8J+OqfCfkLA='

• Decode given Base64 string to byte array. Base64 decoding in browser and node.js.

  data = codec.b64dec('8J+OqfCfkLA=')

  Uint8Array [ 240, 159, 142, 169, 240, 159, 144, 176 ]

  codec.bytesToString(data)

  '🎩🐰'

hex encoding and decoding

• Convert hex-encoded string to a byte representation.

  codec.hexToBytes('cabafa87')

  Uint8Array [ 202, 186, 250, 135 ]

  codec.hexToBytes('0x1234567890ABCDEF')

  Uint8Array [ 18, 52, 86, 120, 144, 171, 205, 239 ]

• Convert byte representation to a hex-encoded string.

  codec.bytesToHex(Uint8Array.from([31, 63, 127, 255]))

  '1f3f7fff'

byte array manipulation

• Concatenate contents of a given byte arrays.

  codec.concatBytes(
      Uint8Array.from([255, 255, 0, 0]),
      codec.stringToBytes('🌍'),
      Uint8Array.from([128, 64])
  )

  Uint8Array [ 255, 255, 0, 0, 240, 159, 140, 141, 128, 64 ]

• Compare two byte arrays.

  codec.compareBytes(
      codec.stringToBytes('𝓬𝓸𝓭𝓮'.normalize('NFC')),
      codec.stringToBytes('𝐜𝐨𝐝𝐞'.normalize('NFC'))
  )

  false

  codec.compareBytes(codec.hexToBytes('0xFF'), Uint8Array.from([255]))

  true

functional programming

• Function composition.

  func.compose(
      string.quote,
      string.shorten
  ) (
      "When I find myself in times of trouble",
      20, string.shorten.END
  )

  '"When I find myself …"'

  stringToHex = func.flow(codec.stringToBytes, codec.bytesToHex)

  [Function]

  stringToHex('Kaboom! 💥')

  '4b61626f6f6d2120f09f92a5'

  func.pipe('4b61626f6f6d2120f09f92a5') (
      codec.hexToBytes, codec.bytesToString
  )

  'Kaboom! 💥'

• Translate the evaluation of function f taking multiple arguments into an evaluation of sequence of functions, each with a single argument.

  addition = (a, b, c) => a + b + c

  [Function: addition]

  func.curry(addition) (1) (2) (3)

  6

• Function arguments rearrangement.

  console.log('a', 'b', 'c', 'd', 'e')

  a b c d e

  revConsole = rearg(console.log) (4, 3, 2, 1, 0)
  revConsole('a', 'b', 'c', 'd', 'e')

  e d c b a

  revConsole('f') ('g', 'h') ('i') ('j')

  j i h g f

• Y-combinator - returns fixed point of a higher-order function passed as f. Anonymous recursion in Javascript.

  factorial = func.Y(r => n => n <= 0  ?  1  :  n * r(n - 1))

  [Function]

  factorial(5)

  120

simple math

• Compute mathematical average of array of numbers.

  math.average([1, 2, 3, 4, 5])

  3

• Base 2 logarithm.

  math.log2(2**32)

  32

• Base 10 logarithm.

  math.log10(1e9)

  9

• Sum of numbers in passed array.

  math.sum([5, 6, 7, 8, 9, 10])

  45

shared memory pattern

Frontend and backend applications often use some globally-configured objects, like axios instance with custom headers and base url, authenticated cloud services provider, express.js instance, database connection object, configured redux store, etc...

One might stick these to window (or global) object, but it's considered anti-pattern.

Another solution is to pass these objects as parameters to functions that needs to use them, but it's cumbersome and scales poorly.

Using memory module solves these problems and reminds the usage of react's hooks.

Example:

• main.js file of an express.js-based microservice application:

  import express, { json } from "express"
  import { share } from "@xcmats/js-toolbox/memory"
  import configureRoutes from "./routes"
  
  // main express application
  const app = express()
  
  // share it with any other module interested
  share({ app })
  
  // some configuration
  app.enable("trust proxy")
  app.use(json())
  
  // complex configuration - e.g. enable CORS,
  // authentication, redirects, etc.
  
  // configureHeaders()
  // configureAuth()
  // configureRedirects()
  
  // ...
  
  // routes configuration
  configureRoutes()
  
  app.listen(/* ... */)

• example routes.js file:

  import { useMemory } from "@xcmats/js-toolbox/memory"
  
  export default configureRoutes () {
  
      // get access to main express application
      const { app } = useMemory()
  
      // add "hello world" route
      app.get("/hello/", (req, res, next) => {
          res.status(200).send({ hello: "world" })
          return next()
      })
  
  }

operating on strings

• Allocate a big string (of size 2^n).

  string.big(5)

  'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx'

• Convert camelText to snake_text.

  string.camelToSnake('someNightsIStayUpCashingInMyBadLuck')

  'some_nights_i_stay_up_cashing_in_my_bad_luck'

• Quote text.

  string.quote('div', '<>')

  '<div>'

• Construct random string of desired length.

  string.random(16)

  'MxWGe8MoOss0yUAP'

• Shorten a given string to the desired length.

  string.shorten('abcdefghijklmnopqrstuvwxyz', 15)

  'abcdefg…tuvwxyz'

  string.shorten(
      'To be, or not to be, that is the question',
      20,
      string.shorten.END
  )

  'To be, or not to be…'

• Convert snake_text to camelText.

  string.snakeToCamel('some_nights_i_call_it_a_draw')

  'someNightsICallItADraw'

data structure manipulation

• Apply path to an object.

  struct.access({ a: { b: { c: 42 } } }, ['a', 'b', 'c'])

  42

• Construct Object from the result of Object.entries() call. entries = [[k1, v1,], ..., [kn, vn,]]

  struct.dict([['a', 'b'], ['c', 'd'], ['e', 'f']])

  { a: 'b', c: 'd', e: 'f' }

• Shallow map (iteration) on objects.

  struct.objectMap(
      { what: 'od', i: '?rof dnats' },
      ([k, v,]) => [
          string.capitalize(k),
          v.split('').reverse().join('')
      ]
  )

  { What: 'do', I: 'stand for?' }

• Swap keys with values in a given Object.

  struct.swap({ a: 'b', c: 'd', e: 'f' })

  { b: 'a', d: 'c', f: 'e' }

type primitives

• Determine if a given value is a proper Number (not NaN and not Infinity).

  [type.isNumber(NaN), type.isNumber(-Infinity), type.isNumber(1234.5678)]

  [ false, false, true ]

• Determine if a given value is an Object (not null, not undefined and not Array).

  [type.isObject(null), type.isObject([]), type.isObject({})]

  [ false, false, true ]

notes

This library is suitable to use in server and browser environments and it is being used as such. Go ahead and file an issue if you found a bug 🐞.

support

You can support this project via stellar network:

• Payment address: xcmats*keybase.io
• Stellar account ID: GBYUN4PMACWBJ2CXVX2KID3WQOONPKZX2UL4J6ODMIRFCYOB3Z3C44UZ

license

js-toolbox is released under the Apache License, Version 2.0. See the LICENSE for more details.