havenwood

def merge_sort array
  return array if array.empty? or array.one?

  sorted = []
  left, right = array.each_slice(array.size.fdiv(2).round).map { |a| merge_sort a }

  loop do
    break sorted.concat(right) if left.empty?
    break sorted.concat(left) if right.empty?

havenwood

module Klass
  def self.new *args, &block
    object = Class.allocate
    object.send :initialize, *args, &block
    object
  end
end

Cat = Klass.new do
  attr_reader :name, :age

havenwood

require 'transducers'

T = Transducers

fizzducer = T.compose T.map { |n| n % 3 == 0 && n % 5 == 0 && 'FizzBuzz' || n },
                      T.map { |n| n % 3 == 0 && 'Fizz' || n },
                      T.map { |n| n % 5 == 0 && 'Buzz' || n },
                      T.map(:to_s)

T.transduce fizzducer, :puts, STDOUT, 1.upto(5)

havenwood

class Proc
  class << self
    def compose *others
      others.map(&:to_proc).inject :*
    end
  end

  def * other
    proc { |*args| other.call self.call *args }
  end

havenwood

class Roshambo
  OPTIONS = [:rock, :paper, :scissors]
  WINNERS = OPTIONS.rotate.zip(OPTIONS).to_h
  LOSERS = WINNERS.invert

  attr_reader :value

  include Comparable

  def initialize value = OPTIONS.sample

havenwood

require 'open-uri'
 
URL = 'https://raw.githubusercontent.com/rubygems/rubygems/master/lib/rubygems/ssl_certs/'
FILENAME = 'AddTrustExternalCARoot-2048.pem'
DIR = File.join RbConfig::CONFIG['rubylibdir'], 'rubygems', 'ssl_certs'
 
pem = open File.join(URL, FILENAME), &:read
File.write File.join(DIR, FILENAME), pem

havenwood

require 'shell'

Shell.verbose = false
Shell.def_system_command 'ls'
Shell.def_system_command 'grep'

sh = Shell.cd Dir.home
sh.transact do
  ls('-a') | grep('^\.') > STDOUT
end

havenwood

require 'shell'

Shell.verbose = false
Shell.def_system_command 'seq'

Shell.new.transact do
  echo(
    seq('100').map(&:to_i).map { |x|
      if x % 15 == 0
        "FizzBuzz"

havenwood

Keybase proof

I hereby claim:

• I am havenwood on github.
• I am havenwood (https://keybase.io/havenwood) on keybase.
• I have a public key whose fingerprint is 06CB 6789 306C 1DC4 BEAE ABF1 CF61 5467 50DB C4B4

To claim this, I am signing this object:

havenwood

function install_pkgsrc() {
  local pkgsrc_url="http://pkgsrc.joyent.com/packages/Darwin/bootstrap"
  local pkgsrc_archive="bootstrap-2015Q2-x86_64.tar.gz"
  local pkgsrc_sha256sum="5e9717932454c6c06db2004a0efe59b40a216aa2c661bc323bd651f8ce4e6c46"
  local pkgsrc_gpgkey="0xDE817B8E"

  echo ">>> Downloading pkgsrc archive for OS X ..."
  \curl -O --progress-bar "$pkgsrc_url/$pkgsrc_archive" || return $?

  echo ">>> Verifying pkgsrc archive SHA256 checksum ..."