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@ClickerMonkey
ClickerMonkey / types.ts
Last active August 8, 2024 00:25
Typescript Helper Types
// when T is any|unknown, Y is returned, otherwise N
type IsAnyUnknown<T, Y, N> = unknown extends T ? Y : N;
// when T is never, Y is returned, otherwise N
type IsNever<T, Y = true, N = false> = [T] extends [never] ? Y : N;
// when T is a tuple, Y is returned, otherwise N
// valid tuples = [string], [string, boolean],
// invalid tuples = [], string[], (string | number)[]
//
// Prelude
// A zero dependency, one file drop in for faster Typescript development with fewer bugs
// through type safe, functional programming. Comments are inline with links to blog posts motiviating the use.
// alias for a function with airity 1
export type Fn<A, B> = (a: A) => B;
// alias for a function with airity 2

In this tutorial we're going to build a set of parser combinators.

What is a parser combinator?

We'll answer the above question in 2 steps.

  1. What is a parser?
  2. and, what is a parser combinator?

So first question: What is parser?

@xem
xem / readme.md
Last active July 1, 2025 21:09
Maths & trigonometry cheat sheet for 2D & 3D games

Conventions

  • A = [xA, yA] is a point on the 2D plane. Same for B, C, ...
  • lengths are in any unit (ex: pixels)
  • code snippets are in JavaScript

Degrees to radians

angleRad = angleDeg * Math.PI / 180;

@paulirish
paulirish / what-forces-layout.md
Last active July 4, 2025 06:51
What forces layout/reflow. The comprehensive list.

What forces layout / reflow

All of the below properties or methods, when requested/called in JavaScript, will trigger the browser to synchronously calculate the style and layout*. This is also called reflow or layout thrashing, and is common performance bottleneck.

Generally, all APIs that synchronously provide layout metrics will trigger forced reflow / layout. Read on for additional cases and details.

Element APIs

Getting box metrics
  • elem.offsetLeft, elem.offsetTop, elem.offsetWidth, elem.offsetHeight, elem.offsetParent
@deandob
deandob / livestream
Created February 26, 2014 22:31
Node.JS function to remux mp4/h.264 video from an IP camera to a HTML5 video tag using FFMPEG
// Live video stream management for HTML5 video. Uses FFMPEG to connect to H.264 camera stream,
// Camera stream is remuxed to a MP4 stream for HTML5 video compatibility and segments are recorded for later playback
var liveStream = function (req, resp) { // handle each client request by instantiating a new FFMPEG instance
// For live streaming, create a fragmented MP4 file with empty moov (no seeking possible).
var reqUrl = url.parse(req.url, true)
var cameraName = typeof reqUrl.pathname === "string" ? reqUrl.pathname.substring(1) : undefined;
if (cameraName) {
try {
cameraName = decodeURIComponent(cameraName);
@ScottPhillips
ScottPhillips / .htaccess
Created February 2, 2012 04:30
Common .htaccess Redirects
#301 Redirects for .htaccess
#Redirect a single page:
Redirect 301 /pagename.php http://www.domain.com/pagename.html
#Redirect an entire site:
Redirect 301 / http://www.domain.com/
#Redirect an entire site to a sub folder
Redirect 301 / http://www.domain.com/subfolder/