havenwood

# An octothorp (#) starts a single-line comment.

=begin
   Starting with a =being and ending with a =end
   makes it a multi-line comment.
=end

##
# 1. Variables and flow control.
#

havenwood

class MyClass
  attr_accessor :user, :type
  def initialize user: 'smith', type: 'pleb'
    @user = user
    @type = type
  end
end
 
both = MyClass.new user: 'blah', type: 'pleb'
just_one = MyClass.new type: 'pleb'

havenwood

str = "aaa [first_name] bar [first_name] [last_name]"
last = str.scan(/\[last_name\]/).size
first = str.scan(/\[first_name\]/).size
remaining = str.gsub(/\[(first_name|last_name)\]/, '').size
first * 15 + last * 10 + remaining

havenwood

require 'benchmark'

hash = {}

Benchmark.measure do
  1_000_000.times do
    hash = {}
  end
end.real
#=> 0.245904

havenwood

def fib n
  a, b = 1, 2
  sum = 0
  while a < n
    sum += a if a.even?
    a, b = b, a + b
  end
  sum
end

havenwood

array = (1..12).map &:to_s

class Array
  def insert_every n, this
    each_slice(n).inject { |r, a| r << this << a }.flatten
  end
end

array.insert_every 3, ','
#=> ["1", "2", "3", ",", "4", "5", "6", ",", "7", "8", "9", ",", "10", "11", "12"]

havenwood

require "./alfred"

results = Alfred::Feedback.new

available_outputs = `./SwitchAudioSource -a | grep "(output)" | sed 's/ (output)$//'`
current_output = `./SwitchAudioSource -c`

def ditch_line available, current
  available.split("\n").delete_if { |line| line == current }.join("\n")
end

havenwood

require 'json'

test2 = {
  :foo1 => {
    :target => "Something1",
    :alias  => "some_alias1"
  },
  :foo2 => {
    :target => "Something2",
    :alias  => "some_alias2"

havenwood

tmux cheatsheet

As configured in my dotfiles.

start new:

tmux

start new with session name:

havenwood

module AtoiString
  refine String do
    def atoi
      fixed_self = fix self
      
      result = 0
      fixed_self.each_char do |c|
        result = result * 10 + c.to_i
      end