dsl.rb

plugin(:echo) do
  name 'Echo Plugin'
  author 'Henrik Hodne <[email protected]>'

  command(:echo, '*') do |from, params|
    from.privmsg(params)
  end
end

oop-dsl.rb

class EchoPlugin < Lime::Plugin
  name 'Echo Plugin'
  author 'Henrik Hodne <[email protected]>'

  command :echo, '*'

  def echo(from, params)
    from.privmsg(params)
  end
end

oop.rb

class EchoPlugin
  def initialize
    Lime.register(:command, :echo, '*', method(:echo))
  end

  def echo(from, params)
    from.privmsg(params)
  end
end