Dan Bamikiya danBamikiya

Array Iteration

https://gist.github.com/ljharb/58faf1cfcb4e6808f74aae4ef7944cff

While attempting to explain JavaScript's reduce method on arrays, conceptually, I came up with the following - hopefully it's helpful; happy to tweak it if anyone has suggestions.

Intro

JavaScript Arrays have lots of built in methods on their prototype. Some of them mutate - ie, they change the underlying array in-place. Luckily, most of them do not - they instead return an entirely distinct array. Since arrays are conceptually a contiguous list of items, it helps code clarity and maintainability a lot to be able to operate on them in a "functional" way. (I'll also insist on referring to an array as a "list" - although in some languages, List is a native data type, in JS and this post, I'm referring to the concept. Everywhere I use the word "list" you can assume I'm talking about a JS Array) This means, to perform a single operation on the list as a whole ("atomically"), and to return a new list - thus making it mu

Semantic versioning regex

^([0-9]+)\.([0-9]+)\.([0-9]+)(?:-([0-9A-Za-z-]+(?:\.[0-9A-Za-z-]+)*))?(?:\+[0-9A-Za-z-]+)?$

example

http://regexr.com/3er1i

also see

Semantic versioning http://semver.org/
Source of the regex npm/node-semver#32

On Good Taste

Linus Torvalds in an interview talked about the idea of good taste in code or what I like to call elegance. As one might expect from two slides meant to make a point during a talk, he omits a lot of details to keep it short and simple. This post digs into the specifics of his example (deleting an element from a list) and adds another example (inserting an element in a list) including working code.

Example from Linus

This is an example of removing an element from a singly-linked list. It's one of the first data structures you learn about when you start learning about computer science and programming. The reason it doesn't show particularly good taste is because we have that condition at the end where we take a different action depending on whether the element we want to remove is at the beginning of the list or somewhere in the middle.

![Bad taste](http://

FWIW: I (@rondy) am not the creator of the content shared here, which is an excerpt from Edmond Lau's book. I simply copied and pasted it from another location and saved it as a personal note, before it gained popularity on news.ycombinator.com. Unfortunately, I cannot recall the exact origin of the original source, nor was I able to find the author's name, so I am can't provide the appropriate credits.

Effective Engineer - Notes

By Edmond Lau
Highly Recommended 👍
http://www.theeffectiveengineer.com/

What's an Effective Engineer?

Route-based chunking

Many of us building single-page apps today use JavaScript module bundling tools that trend towards a monolithic "bundle.js" file including the full app and vendor code for multiple routes. This means if a user lands on any arbitrary route they need to wait for a large bundle of JS to be fetched, parsed and executed before the application is fully rendered and interactive.

This is a little backwards, especially when apps are used under real-world network (3G) and device

Inspired by dannyfritz/commit-message-emoji

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

	/**
	Taken from: http://stackoverflow.com/questions/588040/window-onload-vs-document-onload
	According to Parsing HTML documents - The end,
	The browser parses the HTML source and runs deferred scripts.
	A DOMContentLoaded is dispatched at the document when all the HTML has been parsed and have run. The event bubbles to the window.
	The browser loads resources (like images) that delay the load event.
	A load event is dispatched at the window.
	Therefore, the order of execution will be
	DOMContentLoaded event listeners of window in the capture phase
	DOMContentLoaded event listeners of document

	let getRandomBytes = (
	(typeof self !== 'undefined' && (self.crypto \|\| self.msCrypto))
	? function() { // Browsers
	var crypto = (self.crypto \|\| self.msCrypto), QUOTA = 65536;
	return function(n) {
	var a = new Uint8Array(n);
	for (var i = 0; i < n; i += QUOTA) {
	crypto.getRandomValues(a.subarray(i, i + Math.min(n - i, QUOTA)));
	}
	return a;

Commit type	Emoji
Initial commit	🎉 `:tada:`
Version tag	🔖 `:bookmark:`
New feature	✨ `:sparkles:`
Bugfix	🐛 `:bug:`