citizen428

;;; Ruby/Rails development
 
;; RVM support
;; Ruby Version Manager
(require 'rvm)
(rvm-use-default)
 
;; automatically add 'end' after class, module, def etc.
;; automatically pair braces, single and double quotes
(require 'ruby-electric)

citizen428

# Get the official Emacs repo:
git clone http://repo.or.cz/r/emacs.git/

# Get the fullscreen patch
git remote add typester git://github.com/typester/emacs.git
git fetch typester

# Create a patch and apply to HEAD
# I had merge conflicts when rebasing and 
# build failures for origin/emacs-23

citizen428

Quick Reference

Ruby and Rails

• Ruby
• Rails
• Rails3
• RSpec
• Ruby Toolbox
• Capistrano

citizen428

require 'httparty'

class GitHub
  include HTTParty
  base_uri 'http://github.com/api/v2/yaml'
  
  API_METHODS = {
    :watched => '/repos/watched/' }

  class << self

citizen428

Gist Clients

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Editor Support

• TextMate
• Emacs
• Vim
• Coda

citizen428

user=> ; get the expt funtion
user=> (use '[clojure.contrib.math :only (expt)])
nil
user=> (expt 2 3)
8
user=> ; function to calculate no. of pairs for n people
user=> (defn number-pairs [n] (/ (* n (- n 1)) 2))
#'user/number-pairs
user=> ; how many pairs for 23 people?
user=> (number-pairs 23)

citizen428

class Fixnum
  alias_method :intdiv, :/
  
  def /(divisor)
    (self % divisor) == 0 ? self.intdiv(divisor) : self.to_f/divisor
  end
end

citizen428

user=> ; generate random number
user=> (rand)
0.8545074632292601
user=> ; infinite list of random numbers
user=> ; make sure to set *print-length*
user=> (set! *print-length* 10)
10
user=> (repeatedly rand)
(0.13569783475252373 0.585868618595554 0.7048671603900427 0.1440943435265447 0.24546858003727567 0.15406959135696596 0.41117257771529947 0.1115848319639422 0.669215744258339 0.1521494621978804 ...)
user=> ; get the reductions function from seq-utils

citizen428

(use '(incanter core charts io))
(def usage (read-dataset "report.csv" :header true))

(def instance-types
     (set (filter #(re-find #"BoxUsage" %) ($ :UsageType usage))))

(with-data (->> ($rollup :sum :UsageValue :UsageType usage)
                ($where {:UsageType {:$in instance-types}}))
  (view (bar-chart :UsageType :UsageValue
                   :title "EC Instance Usage"

citizen428

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