task

task.rb

class Task
  def initialize
    @func =->{yield self}
  end
  def update
    @func.call
  end
end

task = []

task << Task.new { p 2 }
task << Task.new { p 4 }
task << Task.new {|o|
  p o
  @n ||= 0
  exit if (@n+=1) > 10
}

task.map &:update until nil