Jin Justin-ZS

This notes is written by Sheldon. You can find me with #iOSBySheldon in Github, Youtube, Facebook, etc.

Need

Convert .mov/.MP4 to .gif

Reason

As a developer, I feel better to upload a short video when I create the pull request to show other viewers what I did in this PR. I tried .mov format directly got after finishing recording screen using Quicktime, however, gif offers preview in most web pages, and has smaller file size.

This is not limited to developer, anyone has this need can use this method to convert the files.

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

The Ultimate Unit Testing Cheat-sheet

Sinon Chai
Chai
Sinon

5 entertaining things you can find with the GitHub Search API

Let's have some command-line fun with curl, [jq][1], and the [new GitHub Search API][2].

Today we're looking for:

The hottest repositories created in the last week.
The oldest user accounts with zero followers. (So sad.)
Issue trends by language.
Clojure projects defying convention.

	// Optional declares a type of keyed type T where all keys are optional.
	// This allows
	type Optional<T> = { [P in keyof T]? :T[P] }

	interface Foo {
	x :number
	y :number
	}

	type OptionalFoo = Optional<Foo>