helpda

simple typescript utility library

getting started

$ npm install helpda

or

$ yarn add helpda

Example Usage

import { sum, map, reduce, sumArr } from 'helpda'

map([1, 2, 3], (x) => x + 1) //[2,3,4]
reduce(sum, 0, [1, 2, 3]) // 6
sumArr([2, 4, 6]) // 12

what function should i use?

| Type | Action | Function | --- | --- | --- | | Array | change every value | map | | compute based on custom function and output the final value | reduce | | flatten return a one-dimensional array, remove nesting | flatten | Object | change every value | map | Functions | memoize | memoize | | revers function args | flip | Logic | | | Math | sum two numbers | sum | | subtract two numbers | subtract | | multiple two numbers | multiple | | divide two numbers | divide | | increment number | inc | | decrement number | dec | | negate number | negate | | get random number between two args | randomN | | sum all number in array | sumArr

API

• Array

map

Map each element of array using a passed callback function.

import { map } from 'helpda'

const array = [1, 2, 3];
const mutiple = x => x * 2;

map(array, mutiple) //[2, 4, 6]

reduce

Reduce compute based on custom function and output the final value.

import { reduce } from 'helpda'

const array = [1, 2, 3];
const sum = (a, b) => a + b

reduce(sum, 0, array) // 6

flatten

flatten return a new one-level array from nested array

import { flatten } from 'helpda'

const array = [1, 2, 3, [4, 5, [6]]];

flatten(array)) // [1, 2, 3, 4, 5, 6]

• Object

• Functions

flip

return a new function with two reversed args

import { flip } from 'helpda'

const divide = (a, b) = a / b)
const flipped = flip((a, b) => a / b);

divide(12, 3) // 4
flipped(12, 3) // 0.25

• Logic

• Math

sum

sum two numbers

import { sum } from 'helpda'

sum(2, 2) // 4

subtract

subtract second arg from first

import { subtract } from 'helpda'

subtract(4, 2) // 2

multiple

multiple two numbers

import { multiple } from 'helpda'

multiple(2, 3) // 6

divide

divide two numbers

import { divide } from 'helpda'

divide(12, 3) // 4

inc

increment number

import { inc } from 'helpda'

inc(13) // 14

dec

decrement number

import { dec } from 'helpda'

dec(13) // 12

negate

negate number

import { dec } from 'helpda'

negate(13) // -13

sumArr

sum all number in an array of numbers

import { sumArr } from 'helpda'

const array = [1, 2, 3, 4, 5];

sumArr(array) // 15

randomN

get random number

import { randomN } from 'helpda'

const min = 0;
const max = 100;

randomN(min, max) // 12..85..3..?