Kimmo Puputti kpuputti

TL;DR: If you want to see me perform a spoken word poem about JavaScript in front of 1000 people (and on video), please ⭐ star this gist. If you're on mobile, you'll need to request desktop site.

JavaScript Slam Poetry

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

	const t = require("tcomb");
	// imstruct is a tcomb type builder that internally builds an
	// Immutable.Record object, but applies tcomb's type system to it
	const imstruct = require("../util/imstruct");

	const Person = imstruct({
	name: t.String,
	age: t.Number
	});

	function range(n) {
	return Array.apply(null, Array(n)).map(function (_, i) { return i })
	}

	function ntuples(n, xs) {
	return range(Math.ceil(xs.length / n)).map(function (i) {
	return xs.slice(i * n, i * n + n)
	})
	}

	function range(/* [begin,] end[, step] */) {
	var begin = arguments.length > 1 ? arguments[0] : 0,
	end = arguments.length > 1 ? arguments[1] : arguments[0],
	step = arguments[2] \|\| 1,
	n = Math.max(0, Math.ceil((end - begin) / step))
	return Array.apply(null, Array(n)).map(function (_, i) {
	return begin + step * i
	})
	}

	// Public domain.
	// Attribution welcome, but not required. -- Pyry Jahkola.


	// What's the point in all this? To get the equivalent of CoffeeScript's
	// (?.) operator into vanilla JavaScript.


	// get(x, key1, key2, ...) -- Get the result of x[key1][key2]..., or undefined.
	// Will short circuit if a key is not found.

	brew update
	brew versions FORMULA
	cd `brew --prefix`
	git checkout HASH Library/Formula/FORMULA.rb # use output of "brew versions"
	brew install FORMULA
	brew switch FORMULA VERSION
	git checkout -- Library/Formula/FORMULA.rb # reset formula

	## Example: Using Subversion 1.6.17
	#

	/*
	* Normalized hide address bar for iOS & Android
	* (c) Scott Jehl, scottjehl.com
	* MIT License
	*/
	(function( win ){
	var doc = win.document;

	// If there's a hash, or addEventListener is undefined, stop here
	if( !location.hash && win.addEventListener ){

	def eq_diff(a, b):
	import json, difflib
	from datetime import datetime

	if a == b:
	return

	class DatetimeEncoder(json.JSONEncoder):
	def default(self, o):
	if isinstance(o, datetime):

	CREATE DATABASE sharetribe_test CHARACTER SET utf8 COLLATE utf8_general_ci;
	CREATE DATABASE sharetribe_development CHARACTER SET utf8 COLLATE utf8_general_ci;
	CREATE DATABASE sharetribe_production CHARACTER SET utf8 COLLATE utf8_general_ci;

	GRANT all privileges ON sharetribe_development.* TO 'sharetribe'@'localhost' IDENTIFIED BY 'put_a_password_here';
	GRANT all privileges ON sharetribe_production.* TO 'sharetribe'@'localhost' IDENTIFIED BY 'put_a_password_here';
	GRANT all privileges ON sharetribe_test.* TO 'sharetribe'@'localhost' IDENTIFIED BY 'put_a_password_here';