scudelletti

Erlang QuickCheck

What is QuickCheck?

QuickCheck is a language for stating properties of programs.

?FORALL(X, nat(), X*X >= 0)

I came across 'bundler/inline' in Bundler pull request 3440, which I'd found from Rails pull request 20429. This now has a little snippet on the What's new page of the Bundler site.

This little example demonstrates how I might use it to create a single file using minitest.

I've just noticed that this script was working for me because I already had minitest installed as a system gem. If I uninstall the gem then the script fails because it can't find minitest. The source code documents an option to install gems if they don't exist (gemfile(true) do) but that doesn't seem to work for me. I see the following error:

Fetching gem metadata from https://rubygems.org/...
Fetching version metadata from https://rubygems.org/..
Resolving dependencies...

Using metaclass 0.0.4

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?

sudo apt-get install xserver-xorg-legacy

Edit /etc/X11/Xwrapper.config

allowed_users=anybody
needs_root_rights=yes

Kubectl output options

Let's look at some basic kubectl output options.

Our intention is to list nodes (with their AWS InstanceId) and Pods (sorted by node).

We can start with:

kubectl get no

To forward X11 from inside a docker container to a host running macOS

Install XQuartz: https://www.xquartz.org/
Launch XQuartz. Under the XQuartz menu, select Preferences
Go to the security tab and ensure "Allow connections from network clients" is checked.
Run xhost + ${hostname} to allow connections to the macOS host *
Setup a HOSTNAME env var export HOSTNAME=`hostname`*
Add the following to your docker-compose:

 environment:

	// How To Use
	// var categories = CategoryModule.Category.all();
	// var categoryComposite = new CategoryModule.CategoryComposite('CategoryComposite', categories.categorias, null);
	//
	// var categoryComposities = categoryComposite.findByName('Bar');
	//
	// var originalCategories = categoryComposities.map(function(item) {
	// return item.original;
	// });

	// Promise.all is good for executing many promises at once
	Promise.all([
	promise1,
	promise2
	]);

	// Promise.resolve is good for wrapping synchronous code
	Promise.resolve().then(function () {
	if (somethingIsNotRight()) {
	throw new Error("I will be rejected asynchronously!");

	# Add this snippet to the top of your playbook.
	# It will install python2 if missing (but checks first so no expensive repeated apt updates)
	# [email protected]

	- hosts: all
	gather_facts: False

	tasks:
	- name: install python 2
	raw: test -e /usr/bin/python \|\| (apt -y update && apt install -y python-minimal)

	function base64url(source) {
	// Encode in classical base64
	encodedSource = CryptoJS.enc.Base64.stringify(source);

	// Remove padding equal characters
	encodedSource = encodedSource.replace(/=+$/, '');

	// Replace characters according to base64url specifications
	encodedSource = encodedSource.replace(/\+/g, '-');
	encodedSource = encodedSource.replace(/\//g, '_');