Nick Fitzsimons NickFitz

#Understanding Cross-browser Scripting

Cross-browser was invented around the turn of the century and is needed more today than ever. Unfortunately, it is also massively misunderstood, both by library developers and their users.

##What Cross-Browser Scripting is Not

Before getting into what cross-browser scripting is, let's look at what it is not. Cross-browser scripting does not imply that scripts will work in every browser and configuration known to man. Certainly a script that does work in every conceivable environment would be considered cross-browser, but such expectations are neither realistic, nor a requirement for a script to be considered cross-browser.

Depsite marketing claims, popular libraries such as jQuery and Lodash are neither cross-browser nor cross-platform. It's critical to understand that they are multi-browser and multi-platform, working in a handful of environments deemed worthy by their authors at the time of each version release. Th

How to recover lost Python source code if it's still resident in-memory

I screwed up using git ("git checkout --" on the wrong file) and managed to delete the code I had just written... but it was still running in a process in a docker container. Here's how I got it back, using https://pypi.python.org/pypi/pyrasite/ and https://pypi.python.org/pypi/uncompyle6

Attach a shell to the docker container

Install GDB (needed by pyrasite)

apt-get update && apt-get install gdb

libdispatch efficiency tips

The libdispatch is one of the most misused API due to the way it was presented to us when it was introduced and for many years after that, and due to the confusing documentation and API. This page is a compilation of important things to know if you're going to use this library. Many references are available at the end of this document pointing to comments from Apple's very own libdispatch maintainer (Pierre Habouzit).

My take-aways are:

You should create very few, long-lived, well-defined queues. These queues should be seen as execution contexts in your program (gui, background work, ...) that benefit from executing in parallel. An important thing to note is that if these queues are all active at once, you will get as many threads running. In most apps, you probably do not need to create more than 3 or 4 queues.
Go serial first, and as you find performance bottle necks, measure why, and if concurrency helps, apply with care, always validating under system pressure. Reuse

58 bytes of CSS to look great nearly everywhere

When making this website, i wanted a simple, reasonable way to make it look good on most displays. Not counting any minimization techniques, the following 58 bytes worked well for me:

main {
  max-width: 38rem;
  padding: 2rem;
  margin: auto;
}

	(function () {
	// If the browser supports Microsoft High Contrast Mode...
	if (window.matchMedia('(-ms-high-contrast: none), (-ms-high-contrast: active)').matches) {
	// Get all the SVGs on the page except the symbol defs
	var svgs = document.querySelectorAll('svg:not(.defs)')

	// ... iterate over SVGs
	Array.prototype.forEach.call(svgs, function(svg) {
	// Set preserveAspectRatio to 'XMidYMin slice'
	svg.setAttribute('preserveAspectRatio', 'xMidYMin slice')

	1. install postgres
	2. run makedb.rb >tiles.csv
	3. run tiles.sql
	4. run archive.rb
	5. enjoy

	#!/bin/bash

	set -e

	CONTENTS=$(tesseract -c language_model_penalty_non_dict_word=0.8 --tessdata-dir /usr/local/share/tessdata/ "$1" stdout -l eng \| xml esc)

	hex=$((cat <<EOF
	<?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">

	with recursive thread as (
	select id, in_reply_to_status_id, 0 as depth
	from tweets
	where in_reply_to_status_id is null
	union
	select tweets.id, tweets.in_reply_to_status_id, 1 + thread.depth as depth
	from thread join tweets on tweets.in_reply_to_status_id = thread.id)
	select * from thread order by depth desc

	Functions

	startElement
	endElement
	_wp_menu_output
	_add_themes_utility_last
	_wp_ajax_delete_comment_response
	_wp_ajax_add_hierarchical_term
	wp_link_manager_disabled_message
	_wp_credits_add_profile_link