VictorTaelin

async/await is just the do-notation of the Promise monad

CertSimple just wrote a blog post arguing ES2017's async/await was the best thing to happen with JavaScript. I wholeheartedly agree.

In short, one of the (few?) good things about JavaScript used to be how well it handled asynchronous requests. This was mostly thanks to its Scheme-inherited implementation of functions and closures. That, though, was also one of its worst faults, because it led to the "callback hell", an seemingly unavoidable pattern that made highly asynchronous JS code almost unreadable. Many solutions attempted to solve that, but most failed. Promises almost did it, but failed too. Finally, async/await is here and, combined with Promises, it solves the problem for good. On this post, I'll explain why that is the case and trace a link between promises, async/await, the do-notation and monads.

First, let's illustrate the 3 styles by implementing

naqvitalha

export const LazyScrollView = forwardRef(function LazyScrollView(
  props: LazyScrollViewProps,
  ref: ForwardedRef<FlashList<unknown[]>>,
): JSX.Element {
  const {children, estimatedScrollViewSize, estimatedItemSize} =
    props;

  const data = isArray(children) ? children : Children.toArray(children);

  // No specific reason for 2000, just a big number. Roughly 2x the screen size

BalogunofAfrica

import { FlashList, FlashListProps } from "@shopify/flash-list";
import React, { forwardRef, ReactElement } from "react";

type ListProps<T> = Omit<FlashListProps<T>, "children"> & { as?: "list" };
type ScrollViewProps<T> = Omit<
  FlashListProps<T>,
  "children" | "data" | "renderItem"
> & {
  as?: "scroll-view";
  children: React.ReactNode | React.ReactNode[];

JeOam

Author: https://www.cyanhall.com/

1. The Layer Tree

Core Animation's original name is Layer Kit

Core Animation is a compositing engine; its job is to compose different pieces of visual content on the screen, and to do so as fast as possible. The content in question is divided into individual layers stored in a hierarchy known as the layer tree. This tree forms the underpinning for all of UIKit, and for everything that you see on the screen in an iOS application.

In UIView, tasks such as rendering, layout and animation are all managed by a Core Animation class called CALayer. The only major feature of UIView that isn’t handled by CALayer is user interaction.

There are four hierarchies, each performing a different role:

Jarred-Sumner

//
//  YeetJSIUTils.h
//  yeet
//
//  Created by Jarred WSumner on 1/30/20.
//  Copyright © 2020 Facebook. All rights reserved.
//

#import <Foundation/Foundation.h>
#import <jsi/jsi.h>

intergalacticspacehighway

import { createContext, forwardRef, useCallback, useMemo } from "react";
import { FlatList, FlatListProps, ViewToken } from "react-native";
import Animated, { useSharedValue } from "react-native-reanimated";

const MAX_VIEWABLE_ITEMS = 4;

type ViewabilityItemsContextType = string[];

export const ViewabilityItemsContext = createContext<
  Animated.SharedValue<ViewabilityItemsContextType>

louy

/**
 * @author Louay Alakkad (github.com/louy)
 * @license MIT https://opensource.org/licenses/MIT
 */
import React from 'react'
import PropTypes from 'prop-types'
import {
  NativeModules,
  ViewProps,
  ViewPropTypes,

Cheesetouched

import { useCallback } from "react";
import { useQueryClient } from "@tanstack/react-query";

export default function useOptimisticUpdate() {
  const queryClient = useQueryClient();

  return useCallback(
    async (queryKey, updater) => {
      await queryClient.cancelQueries({ queryKey });

josephlord

//
//  FetchedResultsControllerPublisher.swift
//  ListsModel
//
//  Created by Joseph Lord on 09/06/2019.
//  Copyright © 2019 Joseph Lord. All rights reserved.
//

import Foundation
import Combine

chrisjacob

Intro

Setup GitHub Pages "gh-pages" branch as a subfolder within the "master" project on your local checkout.

IMPORTANT

If you plan on switching between different branches (e.g. git checkout master-experiment then revert back with git checkout master) you will loose your child folder from this tutorial (because it's in your .gitignore and is not part of your master branch).