gvergnaud

/**
 * # How does `A extends B` work in TypeScript?
 * 
 * If you think about types in terms of sets containing possible values, 
 * the `string` type is the set of all possible strings,
 * the `number` type is the set of all possible numbers,
 * the `'hello'` type is a set containing only the string 'hello'
 * and the `2` type is a set containing only the number 2.
 * 
 * Then you can think of `A extends B` as asking this question:

swyxio

an adaptive, intent based CLI "state machine"

one realization from working on Netlify's CLI is that the CLI framework we used, oclif, didn't provide a great user experience out of the box.

Emphasis on great: it does a lot of nice things, like offering flag and argument parsing, help documentation, and pluggability. That's good for the CLI developer. But what about the CLI user?

• Idiomatic oclif code often checks for required preconditions, and if it doesn't exist, it prints a warning and then process.exit(1).
• Decent code prints a helpful warning telling the user what they got wrong. It is informative.
• Better code offers a prompt, creates a file, or something similar to solve the precondition before proceeding. (possibly recursively). It is intent-based.
• Great code remembers past inputs to prompts and uses that to offer useful defaults. It is adaptive.

threepointone

https://twitter.com/snookca/status/1073299331262889984?s=21

‪“‬In what way is JS any more maintainable than CSS? How does writing CSS in JS make it any more maintainable?”

‪Happy to chat about this. There’s an obvious disclaimer that there’s a cost to css-in-js solutions, but that cost is paid specifically for the benefits it brings; as such it’s useful for some usecases, and not meant as a replacement for all workflows. ‬

‪(These conversations always get heated on twitter, so please believe that I’m here to converse, not to convince. In return, I promise to listen to you too and change my opinions; I’ve had mad respect for you for years and would consider your feedback a gift. Also, some of the stuff I’m writing might seem obvious to you; I’m not trying to tell you if all people of some of the details, but it might be useful to someone else who bumps into this who doesn’t have context)‬

So the big deal about css-in-js (cij) is selectors.

Rich-Harris

I've been deceiving you all. I had you believe that Svelte was a UI framework — unlike React and Vue etc, because it shifts work out of the client and into the compiler, but a framework nonetheless.

But that's not exactly accurate. In my defense, I didn't realise it myself until very recently. But with Svelte 3 around the corner, it's time to come clean about what Svelte really is.

Svelte is a language.

Specifically, Svelte is an attempt to answer a question that many people have asked, and a few have answered: what would it look like if we had a language for describing reactive user interfaces?

A few projects that have answered this question:

swyxio

2019 update: this essay has been updated on my personal site, together with a followup on how to get started

2020 update: I'm now writing a book with updated versions of all these essays and 35 other chapters!!!!

1. Learn in public

If there's a golden rule, it's this one, so I put it first. All the other rules are more or less elaborations of this rule #1.

You already know that you will never be done learning. But most people "learn in private", and lurk. They consume content without creating any themselves. Again, that's fine, but we're here to talk about being in the top quintile. What you do here is to have a habit of creating learning exhaust. Write blogs and tutorials and cheatsheets. Speak at meetups and conferences. Ask and answer things on Stackoverflow or Reddit. (Avoid the walled gardens like Slack and Discourse, they're not public). Make Youtube videos

rosskevin

/* variation on https://medium.com/@DanHomola/react-higher-order-components-in-typescript-made-simple-6f9b55691af1 */
import * as React from 'react'
import { wrapDisplayName } from 'recompose'

// Props you want the resulting component to take (besides the props of the wrapped component)
interface ExternalProps {}

// Props the HOC adds to the wrapped component
export interface InjectedProps {}

ntamvl

Install Multiple Java Versions on macOS High Sierra

Install Homebrew Cask

On Mac, Homebrew is the de-facto package manager, and Homebrew Cask is the app manager. I’m going to use Cask to install Java 7 and 8.

Install Homebrew Cask first if you haven’t:

brew update
brew tap caskroom/cask

Bjvanminnen

Create your app

create-react-app my-app
cd my-app

Eject it, so that we can modify webpack config

npm run eject
y # when prompted

d0ruk

CodeSandbox(CSB) is an online React playground. One of the ways to add a project there is through importing from GitHub. Please sign in via GitHub.

This article will walk through the steps of sync'ing a create-react-app (CRA) project on a GitHub repo with a sandbox.

First, a quick recap of how to use CRA;

>> npm i -g create-react-app

>> create-react-app cra-app

fokusferit

Shallow

Real unit test (isolation, no children render)

Simple shallow

Calls:

• constructor
• render