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curl \                                                                                                                                                20:19:16
    -H "Accept: application/vnd.github.v3+json" \
    # replace :token below with your personal access token
    -H "Authorization: token :token" \ 
    -H "Content-Length: 0" \
    -X PUT \
    # replace ORGNAME with your organization name and USERNAME your username
    https://api.github.com/orgs/ORGNAME/public_members/USERNAME

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const IO = effect =>
  ({
    effect,
    run() {
      return this.effect()
    },
    map(fn) {
      if (!fn ?? typeof fn !== 'function') {
        throw new Error('.map requires a function argument.')
      }

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const quickSort = ([pivot, ...rest]) =>
  pivot
    ? [
        ...quickSort(rest.filter(x => x < pivot)),
        pivot,
        ...quickSort(rest.filter(y => y >= pivot))
      ]
    : []

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const quickSort = (arr, low = 0, high = arr.length - 1) => {
  if (low < high) {
    const p = partition(arr, low, high)
    quickSort(arr, low, p - 1)
    quickSort(arr, p + 1, high)
  }
}

const partition = (arr, low, high) => {
  const pivot = arr[high]

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const quickSort = (arr, low = 0, high = arr.length - 1) => {
  if (low < high) {
    const p = partition(arr, low, high)
    quickSort(arr, low, p)
    quickSort(arr, p + 1, high)
  }
}
const partition = (arr, low, high) => {
  const pivot = arr[Math.floor((high + low) / 2)]
  let i = low

Neo42

React Performance Recipes

Problem: Unnecessary Callback Re-Initiation

When you're using a callback function within useEffect, it's hard to predict how callback function will be modified in the future. Only passing in certain variables from the callback to the deps list won't do. Because once the variables passed in gets removed, your dependencies won't work any more. But you still have to provide some values to the dependency list to sync useEffect with the callback change.

const updateLocalStorage = () => window.localStorage.setItem('count', count)
React.useEffect(() => {
 updateLocalStorage()

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{
  "semi": false,
  "embeddedLanguageFormatting": "off",
  "bracketSpacing": false,
  "jsxBracketSameLine": true,
  "proseWrap": "never",
  "trailingComma": "all",
  "singleQuote": true
}

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const [name, setName] = React.useState(
  someExpensiveComputation(props); // run on every render
)

const [state, setState] = useState(() => {
  const initialState = someExpensiveComputation(props); // only run on the initial render
  return initialState;
});

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import React from "react";

const useStateReducer = (prevState, dispatchArg) =>
  typeof dispatchArg === "function" ? dispatchArg(prevState) : dispatchArg;

const useStateInitializer = (initialArg) =>
  typeof initialArg === "function" ? initialArg() : initialArg;

function useState(initialValue) {
  return React.useReducer(useStateReducer, initialValue, useStateInitializer);

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// Compound Components w/ `React.Children.map` & `React.cloneElement`
import * as React from 'react'
import {Switch} from '../switch'

function Toggle({children}) {
  const [on, setOn] = React.useState(false)
  const toggle = () => setOn(!on)
  return React.Children.map(children, child =>
    // tell if a child is a built-in DOM component
    typeof child.type === 'string'