choallin

class CallbackRegister

  def initialize
    @callbacks = {read: [], write: []}
  end

  def each(type, &block)
    @callbacks[type].each do |callback|
      yield callback
    end

choallin

def process_partial_file_input(data)
  # Do something cool with data
end

# Event loop

big_file = "network/path/big_file.xlsx"
file_handler = open(big_file)
files_to_look_after = [file_handler]

choallin

function x() {
    alert(x);
    var x = "Interesting…"
}

choallin

function x() {
   if(true) {
      var x = "Interesting"
   }
   alert(x);
}

choallin

def multiply_by_two
  multiplicand = 2
  test_method
end

def multiply_by_three
  multiplicand = 3
  test_method
end

choallin

def test_method
  method_variable = 4
  different_variable = [1,2,3]
  different_variable.map do |number|
    number * method_variable
  end
end

choallin

class DoorLock
  def initialize(locked)
    @locked = locked
    @mutex = Mutex.new
  end
  
  def open?
    @mutex.synchronize { !@locked }
  end

choallin

4.times.map do
  t = Thread.current
  t["#{dynamic_variable_name}".to_sym] = method_call
end

joined_threads = threads.map &:join
joined_threads.each do |t|
  # The keys method returns all thread local variables by names
  # analog to the Hash#keys method
  t.keys.each do |key|

choallin

class DoorLock
  def initialize(locked)
    @locked = locked
  end
  
  def open?
    !@locked
  end

  def unlock!

choallin

resource_a = []

threads = []
threads << Thread.new do |t|
  50.times do |i|
    resource_a << i
  end
end

threads << Thread.new do |t|