Tom de Grunt tdegrunt

tmux shortcuts & cheatsheet

start new:

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start new with session name:

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My issues with Modules

In researching topics for RailsCasts I often read code in Rails and other gems. This is a great exercise to do. Not only will you pick up some coding tips, but it can help you better understand what makes code readable.

A common practice to organize code in gems is to divide it into modules. When this is done extensively I find it becomes very difficult to read. Before I explain further, a quick detour on instance_eval.

You can find instance_eval used in many DSLs: from routes to state machines. Here's an example from Thinking Sphinx.

class Article &lt; ActiveRecord::Base

	#!/bin/bash
	LAN_INTERFACE=''
	BRIDGE_INTERFACE=''

	SCRIPT_NAME=$( basename "${0}" )
	POLL_SLEEP_SECONDS=5

	getProcessInfo() {
	local PROCESS="${1}"
	ps -ef \| grep "${PROCESS}" \| grep -v "grep ${PROCESS}"

	#!/usr/bin/env bash
	apt-get install -y python-software-properties build-essential
	apt-add-repository -y ppa:brightbox/ruby-ng
	apt-get update
	apt-get install -y ruby1.9.3
	echo "gem: --no-ri --no-rdoc" >> ~/.gemrc
	gem install chef
	mkdir /etc/chef /var/chef
	cat <<EOF >/etc/chef/solo.rb
	file_cache_path "/var/chef"

	Latency Comparison Numbers (~2012)
	----------------------------------
	L1 cache reference 0.5 ns
	Branch mispredict 5 ns
	L2 cache reference 7 ns 14x L1 cache
	Mutex lock/unlock 25 ns
	Main memory reference 100 ns 20x L2 cache, 200x L1 cache
	Compress 1K bytes with Zippy 3,000 ns 3 us
	Send 1K bytes over 1 Gbps network 10,000 ns 10 us
	Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD

	#!/bin/sh

	###
	# SOME COMMANDS WILL NOT WORK ON macOS (Sierra or newer)
	# For Sierra or newer, see https://github.com/mathiasbynens/dotfiles/blob/master/.macos
	###

	# Alot of these configs have been taken from the various places
	# on the web, most from here
	# https://github.com/mathiasbynens/dotfiles/blob/5b3c8418ed42d93af2e647dc9d122f25cc034871/.osx

	<html>
	<body>

	<!-- really dirty! this is just a test drive ;) -->

	<script type="text/javascript" src="https://raw.github.com/mozilla/pdf.js/gh-pages/build/pdf.js"></script>
	<script type="text/javascript">
	function renderPDF(url, canvasContainer, options) {

	var options = options \|\| { scale: 1 };

	/**
	* I converted the SCSS mixin to LESS for the awesome coders like myself in response to a blog post on 37Signals - http://37signals.com/svn/posts/3271-easy-retina-ready-images-using-scss
	*
	* Update: 2014-08-04 - Updated a long-standing bug where retina images were shown no matter what in the first background-image property.
	* - Updated retina media query to be more reliable ()
	* Update: 2013-11-13 - Picked up another technique thanks to reading this post from Tyler Tate, auto-fill in the second filename for the retina image, http://tylertate.com/blog/2013/06/11/retina-images-using-media-queries-and-LESS-CSS.html
	* Update: 2013-04-16 - Have recently found a few use cases when using a retina pattern from Subtle Patterns on the <body>, this has come in handy
	* Update: 2013-04-05 - Some research in the Wordpress Core(http://core.trac.wordpress.org/ticket/22238#comment:5) was pointed out that some tests may be redundant (Thanks @kbav) so I've cleaned these up
	* Update: 2012-12-29 - U

	#
	# Cookbook Name:: smpostgresql
	# Recipe:: pgdg
	#
	# Copyright 2012-2013 SecondMarket Labs, LLC.
	#
	# Licensed under the Apache License, Version 2.0 (the "License");
	# you may not use this file except in compliance with the License.
	# You may obtain a copy of the License at
	#

	module FullErrorMessages
	extend ActiveSupport::Concern

	# includes errors on this model as well as any nested models
	def all_error_messages
	messages = self.errors.messages.dup
	messages.each do \|column, errors\|
	if self.respond_to?(:"#{column}_attributes=") && (resource = self.send(column))
	messages[column] = resource.errors.messages
	end