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Andrea Giammarchi WebReflection

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WebReflection /
Last active March 5, 2023 19:26
Proposal: an ESX for JS implementation
WebReflection /
Last active November 17, 2022 10:10
Brainstorming a smarter JSX

Brainstorming a smarter JSX


The new proposal and hopefully the new transformer will be out soon.

This gist tries to narrow down all features and complexity hidden behind a smarter JSX, something landed already as @ungap/babel-plugin-transform-hinted-jsx module but not yet concretely, or efficiently, implemented.

WebReflection /
Last active January 21, 2022 11:31
Create wordle report

Apparently there's no share button after wordling in my browsers, so I created this copy/paste JS to put in console, which will produce an output like:

Wordle 212 4/6


A Runtime ImportMap Example

While it's not possible to define a <script type="importmap"> within a module, it is possible to define it in a synchronous <script> tag, as long as it's before any module starts executing.

Example (works in Chrome / Edge)

<!DOCTYPE html>
<html lang="en">
View hooks-in-a-nutshell.js
// WARNING: There's much more to know/do around hooks, and
// this is just a simplification of how these work.
// shared references, updated
// per each hook invoke
let execution = null;
let current = null;
let context = null;
let args = null;
View if-then-else-if-else.js
const If = expression => {
let call = true, value;
return {
then: callback => Promise.resolve(value).then(callback),
Then(callback) {
if (call && expression) {
call = false;
value = callback(expression);
return this;
View async-tag.js
const {isArray} = Array;
const sync = async values => {
for (let {length} = values, i = 0; i < length; i++) {
const value = await values[i];
values[i] = isArray(value) ? await sync(value) : value;
return values;
WebReflection /
Last active September 24, 2021 22:03
My libraries in bytes

Toward better libraries

I am recently re-branding my libraries as µ (micro), refactoring these when necessary, dropping IE < 11 support, improving the logic where possible, or providing a better, more robust, or faster, API.

In few words, on the right there is the modern version of libraries I've used for the last ~5 years in production or for side projects, and I suggest anyone having one of the earlier dependencies, to have a look at their modern, micro, counterpart.

How to read these tables

All sizes are minified, brotli compressed, and representing these two files, when possible:

View use-state-caller.js
function useState(value) {
const {caller} = arguments.callee;
const {arguments: a} = caller;
const {stack} = useState;
if (!stack.has(caller))
stack.set(caller, {a, i: 0, s: []});
const state = stack.get(caller);
state.a = a;
const {i, s} = state;
if (i === s.length) {
WebReflection /
Last active December 1, 2020 14:14
A privileged answer to a well known issue.

This site throws in users and, most importantly, developers face, the fact publishing websites with hundreds of JS Kilobytes just to see some content, content that might also break due JS itself or browsers that haven't been tested or targeted, is very bad.

The same site is also great to remind everyone that a11y (accessibility) matters, and if you got upset by its disruptive technique, and you are a Web developer, now you know how it feels for people incapable of surfing the "modern Web" with its overly-bloated frameworks and practices that way too often don't take a11y into account.

However, JS is not to blame here, while developers abusing JS without following graceful enhancement practices, or without testing their sites offer some meaningful content even for users that might have disabled JS for whatever reason, are to blame so ... please "don't be that kind of developer".

That being said, as an exercise to see if I could surf it via JS, I've created this ti