havenwood

class MultipleInstancesOfState
  attr_accessor :state

  def initialize(state:)
    @state = state
  end

  def foo
    @state.reverse!
  end

havenwood

git clone --depth 1 --single-branch --branch guild https://github.com/ko1/ruby.git ruby-isolates-src
cd ruby-isolates-src
autoconf
./configure --prefix=$HOME/.rubies/ruby-guilds # chruby
# ./configure --prefix=$HOME/.rvm/rubies/ruby-guilds # RVM
# ./configure --prefix=$HOME/.rbenv/versions/3.0.0/ruby-guilds # rbenv
make -j2
make install

havenwood

require 'time'

module FixStrptime
  refine Time.singleton_class do
    def strptime(date, format, now=self.now)
      d = Date._strptime(date, format)
      raise ArgumentError, "invalid date or strptime format - `#{date}' `#{format}'" unless d
      if seconds = d[:seconds]
        if sec_fraction = d[:sec_fraction]
          usec = sec_fraction * 1000000

havenwood

# frozen_string_literal: true

require 'benchmark/ips'

Benchmark.ips do |ips|
  words = [*'a'..'all'].freeze
  separator = '-'

  ips.report('map & join') { words.map { |word| separator + word }.join }
  ips.report('join & prepend') { words.join(separator).prepend(separator) }

havenwood

# frozen_string_literal: true

require 'delegate'

class Fiberator < DelegateClass Fiber
  class Rewind < StandardError
  end
  NOTHING = Object.new
  private_constant :NOTHING

havenwood

# Ruby 1.9
Hash[collection.group_by { |n| n }.map { |k, v| [k, v.size] }]

# Ruby 2.0 Array#to_h
collection.group_by { |n| n }.map { |k, v| [k, v.size] }.to_h

# Ruby 2.2 Object#itself
collection.group_by(&:itself).map { |k, v| [k, v.size] }.to_h

# Ruby 2.4 Hash#transform_values

havenwood

module RedInspect
  REFINED = [NilClass, Array, Array.singleton_class].freeze

  def inspect
    "\e[91m#{super}\e[0m"
  end

  self.then do |oneself|
    REFINED.each { refine(_1) { include oneself } }
  end

havenwood

module SizeSquared
  [String, Enumerable].each do |this_class|
    refine this_class do
      def size_squared
        size.abs2
      end
      alias length_squared size_squared
    end
  end
end

havenwood

# frozen_string_literal: true

fetcher = Gem::SpecFetcher.fetcher

matches = fetcher.detect do |spec|
  spec.name.start_with? 'jekyll-'
end

plugins = matches.map(&:first).map(&:name).uniq

havenwood

require 'async'
require 'async/notification'

def do_a_thing_lasting(duration)
  puts 'hi'
  sleep duration
  puts 'bye'
end

def now_and_every(interval)