Willem van Ketwich wilvk

JavaScript function hoisting by example

Below are many examples of function hoisting behavior in JavaScript. Ones marked as works successfuly print 'hi!' without errors.

To play around with these examples (recommended) clone them with git and execute them with e.g. node a.js

Notes on hoisting

(I may be using incorrect terms below, please forgive me)

compile full Vim

The default Vim installed on most Linux distros lacks a number of vital features, like xterm_clipboard (allows copy-and-pasting to the system clipboard) and python (on which certain plugins rely). The compile_full_vim.sh shell script removes the currently installed Vim and compiles a full-featured version; it's based entirely off Valloric's YouCompleteMe walkthrough, which it bundles into a simple script for convenience. Vim will be compiled with the following feature flags:

--with-features=huge
--enable-multibyte

Dependency Injection in Ruby 07 Oct 04

Introduction

At the 2004 Ruby Conference, Jamis Buck had the unenviable task to explain Dependency Injection to a bunch of Ruby developers. First of all, Dependency Injection (DI) and Inversion of Control (IoC) is hard to explain, the benefits are subtle and the dynamic nature of Ruby make those benefits even more marginal. Furthermore examples using DI/IoC are either too simple (and don’t convey the usefulness) or too complex (and difficult to explain in the space of an article or presentation). I once attempted to explain DI/IoC to a room of Java programmers (see onestepback.org/articles/dependencyinjection/), so I can’t pass up trying to explain it to Ruby developers.

Thanks goes to Jamis Buck (the author of the Copland DI/IoC framework) who took the time to review this article and provide feedback.

What is Dependency Injection?

Working with ansible-vault

I've been using a lot of Ansible lately and while almost everything has been great, finding a clean way to implement ansible-vault wasn't immediately apparent.

What I decided on was the following: put your secret information into a vars file, reference that vars file from your task, and encrypt the whole vars file using ansible-vault encrypt.

Let's use an example: You're writing an Ansible role and want to encrypt the spoiler for the movie Aliens.

Removing the last commit

To remove the last commit from git, you can simply run git reset --hard HEAD^ If you are removing multiple commits from the top, you can run git reset --hard HEAD~2 to remove the last two commits. You can increase the number to remove even more commits.

If you want to "uncommit" the commits, but keep the changes around for reworking, remove the "--hard": git reset HEAD^ which will evict the commits from the branch and from the index, but leave the working tree around.

If you want to save the commits on a new branch name, then run git branch newbranchname before doing the git reset.

	#!/usr/bin/env python2

	import SimpleHTTPServer
	import SocketServer
	import logging

	PORT = 8000

	class GetHandler(SimpleHTTPServer.SimpleHTTPRequestHandler):


	location ~* ^/s3/(.*) {
	set $bucket '<REPLACE WITH YOUR S3 BUCKET NAME>';
	set $aws_access '<REPLACE WITH YOUR AWS ACCESS KEY>';
	set $aws_secret '<REPLACE WITH YOUR AWS SECRET KEY>';
	set $url_full "$1";
	set_by_lua $now "return ngx.cookie_time(ngx.time())";
	set $string_to_sign "$request_method\n\n\n\nx-amz-date:${now}\n/$bucket/$url_full";
	set_hmac_sha1 $aws_signature $aws_secret $string_to_sign;
	set_encode_base64 $aws_signature $aws_signature;

	- name: ensure all dir permissions are set correctly
	shell: find /my/dir -type d -print0 \| xargs -0 chmod -c 2755
	register: chmod_result
	changed_when: "chmod_result.stdout != \"\""

	- name: ensure all file permissions are set correctly
	shell: find /my/dir -type f -print0 \| xargs -0 chmod -c 0650
	register: chmod_result
	changed_when: "chmod_result.stdout != \"\""

	#!/bin/bash
	#
	# Bash script to setup headless Selenium (uses Xvfb and Chrome)
	# (Tested on Ubuntu 12.04) trying on ubuntu server 14.04

	# Add Google Chrome's repo to sources.list
	echo "deb http://dl.google.com/linux/chrome/deb/ stable main" \| sudo tee -a /etc/apt/sources.list

	# Install Google's public key used for signing packages (e.g. Chrome)
	# (Source: http://www.google.com/linuxrepositories/)