layout.rb

require 'mustache'

class Layout < Mustache
  self.template = "Header
{{{yield}}}
Footer"
end

class Index < Mustache
  self.template = "The Index."
end

class Profile < Mustache
  self.template = "The Profile."
end


def render(klass)
  view = Layout.new
  view[:yield] = klass.render
  view.render
end

puts "Index:"
puts render(Index)

puts

puts "Profile:"
puts render(Profile)