Shinpeim

a = ->{10}
b = ->{10}
c = ->{a.call + b.call}
puts c.call # => 20

a = ->{20}
puts c.call # => 30

Shinpeim

require 'observer'
class ReactiveValue
  include Observable

  attr_reader :value

  def set(value)
    @value = value
    changed
    notify_observers(self)

Shinpeim

def try_something
  begin
    nyan
  rescue
    begin
      wan
    rescue
      piyo
    end
  end

Shinpeim

class Solver
  def initialize(open_char, close_char)
    @open_char  = open_char
    @close_char = close_char
    @count = 0
  end

  def run(string)
    chars = string.split("")
    chars.each do |char|

Shinpeim

/*
* here is comment
*/
// needed to compile comment
/*
* here is comment
*/
// needed to compile comment
1;

Shinpeim

class Collision < StandardError; end

  def generate_random_string
  raise Collision;
end

def nyan(retries = 10)
  s = generate_random_string
rescue Collision => e
  p "コリジョンが発生しました"

Shinpeim

class Collision < StandardError; end

def generate_random_string
  raise Collision;
end

def nyan(retries = 10)
  s = generate_random_string
rescue Collision => e
  p "コリジョンが発生しました"

Shinpeim

object Nyan {
  class A {
    def nyan = "A"
  }

  implicit class B (self:A){
    def nyan = "B"
    def wan = "B"
  }

Shinpeim

object DecoratorSample extends App{
  val nyan: Nyan = new NyanImpl
  nyan.nyan("にゃーん") // => にゃーん

  val nyanWithDecorator: Nyan = new NyanDecorator(new NyanImpl)
  nyanWithDecorator.nyan("にゃーん") // => にゃーんなのです

  // という感じで、既存のクラス（NyanImpl)を書き換えずに、
  // その動きを変える（拡張する）ことができるのが
  // デコレーターパターン

Shinpeim

trait Nyan {
  def nyan(arg: String): String
}

// デコレーターで拡張される側のクラス
class NyanImpl extends Nyan {
  def nyan(arg: String): String = {
    arg + "にゃーん"
  }
}