gistfile1.rbx

require 'erb'

local_assigns = {:a => 10, :b => 20}
locals_code = local_assigns.keys.map { |key| "#{key} = local_assigns[:#{key}];" }.join

source = "<%= whatever_is_in_your_template %>"
compiled_source = ERB.new(source).src

method_name = 'derived_from_template_name_and_local_keys'
compiled_method_source = source = <<-end_src
  def #{method_name}(local_assigns)
    old_output_buffer = output_buffer;#{locals_code};#{compiled_source}
  ensure
    self.output_buffer = old_output_buffer
  end
end_src

puts compiled_method_source