Skip to content

Instantly share code, notes, and snippets.

Domenic Denicola domenic

View GitHub Profile
domenic /
Last active Jan 16, 2019
Set.prototype.difference, simplified


Proposed spec texts

Set.prototype.difference(arg), minimalist

  1. If Type(this) is not Object, or this does not have a [[SetData]] internal slot, throw a new TypeError exception.
  2. If Type(arg) is not Object, or arg does not have a [[SetData]] internal slot, throw a new TypeError exception.
  3. Let diffList be a List containing all elements that are in this.[[SetData]] but are not in arg.[[SetData]], using SameValueZero to determine identity. (Optional: formalize this with a loop that operates on the Lists.)
  4. Let newSet be ? OrdinaryCreateFromConstructor(%Set%, "%SetPrototype%", « [[SetData]] »).
domenic /
Last active Dec 22, 2018
Revamping link fetching and stuff
domenic / html-style.html
Created Jul 31, 2018
HTML Standard inline stylesheet
View html-style.html
.status { min-height: 0.6em; font: 1em sans-serif; width: 9em; padding: 0.3em; position: absolute; z-index: 8; right: 0.3em; background: #EEE; color: black; box-shadow: 0 0 3px #999; overflow: hidden; margin: -2em 0 0 0; border-collapse: initial; border-spacing: initial; }
.status:hover { z-index: 9; }
.status:focus-within { z-index: 9; }
.status.wrapped > :not(input) { display: none; }
.status > input { position: absolute; left: 0; top: 0; width: 1em; height: 1em; border: none; background: transparent; padding: 0; margin: 0; }
.status > p { font-size: 0.6em; margin: 0; padding: 0; }
.status > p + p { padding-top: 0.5em; }
.status > p > strong { margin-left: 1.5em; }
.status > .support { display: block; }
domenic / transfer.js
Created Jul 26, 2018
ArrayBuffer.prototype.transfer not-really-a-polyfill
View transfer.js
// This creates a copy, but does detach the source buffer
const mc = new MessageChannel();
ArrayBuffer.prototype.transfer = function () {
const result = this.slice();
mc.port1.postMessage(this, [this]);
return result;
domenic / arch.js
Created Jun 3, 2018
Mozilla arch JS code
View arch.js
function curveInArchCoords(col, rows, cols) {
const mathX = col / cols * 2 * Math.PI;
const mathY = Math.cos(mathX);
const archY = (1 + mathY) / 2 * rows;
return archY;
function setFrame(frame, rows, cols, colOffset) {
for (const i of frame) {
frame[i] = 0;
View HTMLMarqueeElement.js
"use strict";
const conversions = require("webidl-conversions");
const utils = require("./utils.js");
const impl = utils.implSymbol;
const HTMLElement = require("./HTMLElement.js");
function HTMLMarqueeElement() {
throw new TypeError("Illegal constructor");
domenic / infinite-list-with-shadow-stuff.html
Last active Mar 7, 2018
View infinite-list-with-shadow-stuff.html
<!-- Clean light DOM: -->
<std-list id="list">
<div class="item">0 - Domenic</div>
<div class="item">1 - Ojan</div>
<div class="item">2 - Drew</div>
<div class="item">3 - Kevin</div>
<div class="item">4 - Gray</div>
<!-- Via this structure: -->
domenic /
Last active Nov 30, 2017
Contra Bruce Lawson's "Editing the W3C HTML5 spec"

A response to

Unfortunately this post contains a lot of inaccuracies. For example, the claim that the WHATWG HTML Standard is future-facing and for incubation is false. Such additions are explicitly against the WHATWG working mode: see the sections on Additions and New Proposals.

It also misunderstands the outline algorithm, which isn't a requirement on browsers, but instead guidance for developers as to how to structure their pages. As such it's not some kind of speculative browser feature as this post characterizes it. (It's bad guidance for developers—but the proper fix for that isn't to include some warning box saying "this feature, which isn't meant for browsers anyway, isn't implemented in browsers" like the W3C HTML fork does. The proper fix is outlined <a href="

domenic / private-static-1.js
Created Nov 30, 2017
Why private static methods are important
View private-static-1.js
// Today, with underscore-prefixed "private"
class Point {
constructor(x, y) {
this._x = x;
this._y = y;
length() {
return Math.sqrt(squareLengthHelper(this));
domenic /
Created Oct 5, 2017
FTL implies causality violation

(From a friend one mine; I'm just hosting this here.)

Issue 1: Relativity of Simultaneousness:

Your buddy Einstein is riding the interstellar express train. All the lights are off, but just as it passes your observation platform, he turns on a lamp in the middle of the train. You and he have taken bets on which end of the train, front or back, will light up first. As expected, your video cameras on the platform record the rear of the train lighting up first, since, as the light spreads out from the original location of the lamp, the rear of the train moves slightly closer to the source, while the front end is moving away. However, Einstein reports that his equipment shows both ends lit up simultaneously.

Both of you are correct. In your reference frame the events "light reaches front of train" and "light reaches rear of train" are not simultaneous, even though in Einstein's they are are.

Issue 2: Superluminal Travel

You can’t perform that action at this time.