ruby_js_nonsense.ruby

console = Object.new
def console.log(*x)
  puts x.map(&:to_s).join(',')
end

class Object
  def method_missing(*args)
    return args[0]
  end
end

def function(*args, &block)
  func_name = :"func_#{rand(1000000)}"
  impl_name = :"func_#{rand(1000000)}"

  klass = Class.new { attr_accessor *args }
  function_block = Proc.new { |*arg_values|
    obj = klass.new
    klass.send(:define_method, impl_method_name, &block)
    args.zip(arg_values).each {|arg, arg_value| obj.send(:"#{arg}=", arg_value) }
    obj.send(impl_method_name)
  }

  define_method(func_name, &function_block)

  func_name
end

define_method(:var) { |random_function_name|
  var_name = local_variables.find do |local_var|
    local_var != :random_function_name && eval(local_var.to_s) == random_function_name
  end
  define_method(var_name) { |*args|
    send(random_function_name, *args)
  }
}

var foo = function(a, b) {
  return a + b
}

var first = 3;
var second = 4;

var sum = function(a, b) {
  a + b;
}

console.log("Sum = ", sum(first, second));

I think you'll want to define your method_missing function on object as:

class Object
  def method_missing(*args)
    skip_methods = %i(to_a to_hash to_io to_str to_ary to_int)
    return nil if skip_methods.include?(args[0])

    return args[0]
  end
end

...like you did in your talk.

Great presentation, btw! My favorite one that I saw at RubyConf!