paulirish

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

brycebaril

@mafintosh asks: "Does anyone have a good code example of when to use setImmediate instead of nextTick?"

https://twitter.com/mafintosh/status/624590818125352960

The answer is "generally anywhere outside of core".

process.nextTick is barely asynchronous. Flow-wise it is asynchronous, but it will trigger before any other asynchronous events can (timers, io, etc.) and thus can starve the event loop.

In this script I show a starved event loop where I just synchronously block, use nextTick and setImmediate

Munter

var jspm = require('../package.json').jspm;
var jsdom = require('jsdom');
var async = require('async');
var chalk = require('chalk');

var express = require('express');
var app = express();

app
  .get('*.html', function (req, res) {

tkadlec

(function () {
	var perfBar = function(budget) {

		window.onload = function() {
			window.performance = window.performance || window.mozPerformance || window.msPerformance || window.webkitPerformance || {};


			var timing = window.performance.timing,
			now = new Date().getTime(),
			output, loadTime;

bendc

// array utils
// =================================================================================================

const combine = (...arrays) => [].concat(...arrays);

const compact = arr => arr.filter(Boolean);

const contains = (() => Array.prototype.includes
  ? (arr, value) => arr.includes(value)
  : (arr, value) => arr.some(el => el === value)

jkrems

In all the discussions about ES6 one thing is bugging me. I'm picking one random comment here from this io.js issue but it's something that comes up over and over again:

There's sentiment from one group that Node should have full support for Promises. While at the same time another group wants generator syntax support (e.g. var f = yield fs.stat(...)).

People keep putting generators, callbacks, co, thunks, control flow libraries, and promises into one bucket. If you read that list and you think "well, they are all kind of doing the same thing", then this is to you.

jennybc

Finessing Excel's stupid line endings

I am sheepish to admit a certain type of routine Microsoft Excel use.

Current example: I am marking for STAT 545. I use R to create a comma delimited marking sheet, by joining the official class list and peer reviews. The sheet contains variables, initially set to NA, where the TAs and I enter official marks and optional comments.

This is where Excel comes in. I like its visual organization of this comma delimited file much more than, say, using a plain text editor. I use the ability to hide columns, resize columns, wrap text, and (gasp!) even fill rows with grey to indicate I am done.

I keep saving the file as comma delimited and I put up with Excel's incessant freak out about "losing features". This is not a one time thing. I need to save and commit this file many times before it is considered done.

adambard

(ns whatlang.core
  (:require [clojure.java.io :as io]
            [clojure.string :as str]
            [clojure.set :as sets]
            ))

(defn load-data
  "Read the country data file from the resource. The data has been
  mangled in to lines like so:

ryboe

OBSOLETE PREFIXES
    -xv-interpret-as      // -xv- and -o- are old Opera prefixes for the Presto
    -xv-phonemes          // engine. Opera switched to the Blink engine with
    -xv-voice-balance     // version 15. The current version is 34.
    -xv-voice-duration
    -xv-voice-pitch
    -xv-voice-pitch-range
    -xv-voice-rate
    -xv-voice-stress
    -xv-voice-volume

dawogfather

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>name</key>
	<string>Comments</string>
	<key>scope</key>
	<string>source.java-props</string>
	<key>settings</key>
	<dict>