Examples to not forget metaprogramming

metaprog.rb

# Some examples to not forget Ruby metaprogramming
class Uno
end

module ExtendMethods
  def self.included(base)
    base.send(:include, ClassMethods)
    base.send(:extend, InstanceMethods)
  end

  module ClassMethods
    def hello
      puts "Hello from class methods"
    end

    ["hola", "jeje"].each do |v|
      class_eval <<-CODE, __FILE__, __LINE__ + 1
        def #{v}
          puts "#{v}"
        end
      CODE
    end
  end

  module InstanceMethods
    def hello
      puts "Hello from instance method"
    end
  end
end

Uno.send(:include, ExtendMethods)

uno = Uno.new
uno.hello
Uno.hello

uno.hola

module InstanceEval
  def eval_methods(&block)
    instance_eval &block
  end
end

Uno.send(:include, InstanceEval)

uno.eval_methods do
  puts "-------DSL like Instance eval-------"
  hola
  hello
end