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/**
 * Converts an RGB color value to HSL. Conversion formula
 * adapted from http://en.wikipedia.org/wiki/HSL_color_space.
 * Assumes r, g, and b are contained in the set [0, 255] and
 * returns h, s, and l in the set [0, 1].
 *
 * @param   Number  r       The red color value
 * @param   Number  g       The green color value
 * @param   Number  b       The blue color value
 * @return  Array           The HSL representation

mjackson

Composing <Route> in React Router v6

Composition of <Route> elements in React Router is changing in v6 from how it worked in v4/5 and in Reach Router. React Router v6 is the successor of both React Router v5 and Reach Router.

This document explains our rationale for making the change as well as a pattern you will want to avoid in v6 and a note on how you can start preparing your v5 app for v6 today.

Background

In React Router v5, we had an example of how you could create a element](https://github.com/remix-run/react-router/blob/320be7afe44249d5c025659bc00c3276a19f0af9/packages/react-router-dom/examples/Auth.js#L50-L52) to restrict access to certain routes on the page. This element was a simple [wrapper around an actual element that made a simple decision: is the user authenticated or not? If so, ren

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#!/bin/bash

# To install: just copy this script to your machine and name it whatever you want.
# Let's say you named it toggle-desktop-icons.sh, then all you need to do is make
# the script executable, like this:
#
# chmod +x toggle-desktop-icons.sh
#
# Now you can execute the script directly in the terminal any time you want to
# show/hide the desktop icons, like this:

mjackson

import { useState, useEffect, useCallback } from 'react'

function usePromise(createPromise) {
  const [error, setError] = useState()
  const [value, setValue] = useState()

  useEffect(() => {
    let current = true

    createPromise().then(

mjackson

#!/bin/sh

# This script should be saved in a git repo as a hook file, e.g. .git/hooks/pre-receive.
# It looks for scripts in the .git/hooks/pre-receive.d directory and executes them in order,
# passing along stdin. If any script exits with a non-zero status, this script exits.

script_dir=$(dirname $0)
hook_name=$(basename $0)

hook_dir="$script_dir/$hook_name.d"

mjackson

Redirects in React Router v6

An important part of "routing" is handling redirects. Redirects usually happen when you want to preserve an old link and send all the traffic bound for that destination to some new URL so you don't end up with broken links.

The way we recommend handling redirects has changed in React Router v6. This document explains why.

Background

In React Router v4/5 (they have the same API, you can read about why we had to bump the major version here) we had a <Redirect> component that you could use to tell the router when to automatically redirect to another URL. You might have used it like this:

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var PIXI = require('pixi.js')
console.log(PIXI)

mjackson

// I was trying to optimize some redux queries the other day when
// the thought occurred to me that it would be nice if redux let
// you know *what keys* changed instead of just letting you know that
// there was *some* kind of change.

// I was reminded of Redis' "keyspace notifications" (http://redis.io/topics/notifications)
// that can be used to get notifications about changes in the Redis
// keyspace, and I thought maybe we could try a similar idea in redux.

// So I wrote this little homegrown version of redux, with support for

mjackson

import React from 'react';

let DataContext = React.createContext();

// A higher-order component for pairing preload function + component ...
function withData(preloadData, Component, autoPreloadOnRender = true) {
  let needsPreload = !!autoPreloadOnRender;

  let promise;
  let value;

mjackson

const npmApiUrl = "https://api.npmjs.org/downloads/point";

async function fetchDownloadCounts(packageName, year) {
  let range = `${year}-01-01:${year}-12-31`;
  let response = await fetch(`${npmApiUrl}/${range}/${packageName}`);
  return (await response.json()).downloads;
}

async function getDownloads(startYear, endYear = startYear) {
  if (endYear < startYear) {