ljharb

Commit Message Conventions

This is a rough sketch of the commit message conventions I follow.

Format

[$Category] `$Component`: short summary

Fixes #123. See #456.

ljharb

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

ljharb

> Object.defineProperty(Object.prototype, 'a', { set: function (v) { throw new Error(v); } });
{}
> Object.getOwnPropertyNames({})
[]
> Object.getOwnPropertyNames({a: 1})
Error: true
    at Object.defineProperty.set (repl:1:74)
    at Function.getOwnPropertyNames (native)
    at repl:1:9
    at REPLServer.self.eval (repl.js:110:21)

ljharb

function formatValue(x) {
	var ret;

	if (typeof x == "string") {
		return "'" + x.replace(/\n/g,"\\n") + "'";
	}
	if (typeof x == "number" && x === 0 && (1/x === -Infinity)) {
		return "-0";
	}
	if (Array.isArray(x)) {

ljharb

Keybase proof

I hereby claim:

• I am ljharb on github.
• I am ljharb (https://keybase.io/ljharb) on keybase.
• I have a public key whose fingerprint is F208 CF4D F9AF 4C98 82F5 C737 DD6C DDD3 CBBB C186

To claim this, I am signing this object:

ljharb

var promises = [
	async1(),
	async2(),
	…
	asyncN()
];
/* jQuery: warning, won't swallow exceptions */
	var deferred = $.Deferred();
	$.when.apply($, promises)
		.done(function () { deferred.resolve(promises); })

ljharb

// because of declaration hoisting, wherever we put `filter()`, it
// will be declared for a longer lifetime than is necessary.
//
// inline function expression (or arrow function) inside the loop
// isn't the answer, because then you recreate the function over
// and over again.

function doSomething() {
	var items = [], i, ret = 0;
	

ljharb

(function ($) {
	var keys = [], code = '38,38,40,40,37,39,37,39,66,65';
    var konami = function (e) {
		keys.push(e.which);
		if (keys.length >= 11 && keys.slice(-11).toString() !== code) {
			keys = [];
			/* do your konami thing here */
		} else if (keys.length > 11) {
			keys.length = 11;
		}

ljharb

/*global setTimeout */
var Queue = function Queue(q) {
  "use strict";
  // (C) WebReflection - Mit Style License
  var callback,
    next = function next() {
      callback = q.shift();
      if (callback) { callback(q); }
      return !!callback;
    };

ljharb

var EventEmitter = require("events").EventEmitter;

var emitter = new EventEmitter();

var foo = function () {
  console.log("foo");
};
emitter.once("foo", foo);

var bar = function () {