JavaScript

Matt Smith on when to use map() vs. forEach() in JavaScript. Just one of those things I can imagine asking or being asked in a coding interview. Some interesting comments below the article as well.

It’s not particularly obvious, but a child’s useEffect will run before a parent’s will. Let’s look at why.

What is the difference between ESLint and TypeScript? Perhaps that feels like a strange question as ESLint is a, uhm, linter, and TypeScript is a language that compiles to JavaScript. Josh Goldberg writes how there is some overlap: While ESLint and TypeScript operate differently and specialize in different areas of code defects, there is some […]

I enjoyed this blog post from Blake Watson about a simple requirement and then going down the rabbit hole of functional programming to solve it in increasingly reusable, if mind-bending ways. By the end: Creating a function that returns a function that returns a function can get a little trippy to think about. But what […]

Allen Pike “after about a decade away from regularly writing JavaScript” comes back to take a look. I think these points are all correct: The goal was to see if there was an obvious (boring, trodden) framework, and the answer is… kinda?

There are quite a few tools to avoid *needing* a database these days, static site generators chief among them. So then what are the things that push toward or require a database?

I can imagine being asked at an interview: What’s the difference between JavaScript engines and JavaScript runtimes? Nicholas C. Zakas says: A JavaScript engine implements ECMAScript as defined by the ECMA-262 standard. ECMA-262 defines the core functionality of JavaScript without any affordances for input or output. A JavaScript runtime is an ECMAScript host that embeds […]

How many ways are there to add an event (like a click) to an element? Andrea Giammarchi covers them. The first two are basically the same (hence the “2.5” in the title). I’d say the vast majority of event handling is through addEventListener, but the clearly listed advantages/disadvantages Andrea goes through are worth understanding. The […]

Pretty interesting trickery here, encoding a secret message in an emoji that you automatically get when you copy/paste it from Paul Butler. Most unicode characters do not have variations associated with them. Since unicode is an evolving standard and aims to be future-compatible, variation selectors are supposed to be preserved during transformations, even if their […]

For who-knows-what reason color inputs only show a color swatch, not a string representation of the color. Let’s see if we can fix that.