class Temple::Filters::Escapable

def compile(exp)
  return exp if !exp.is_a?(Enumerable) || exp.is_a?(String)
  
  if is_escape?(exp)
    case exp[1][0]
    when :static
      [:static, eval(@escaper % exp[1][1].inspect)]
    when :dynamic, :block
      [exp[1][0], @escaper % exp[1][1]]
    else
      raise "Escapable can only handle :static, :dynamic and :block for the moment."
    end
  else
    exp.map { |e| compile(e) }
  end
end

def initialize(options = {})
  @escaper = options[:escaper] || 'CGI.escapeHTML((%s).to_s)'
end

def is_escape?(exp)
  exp.respond_to?(:[]) && exp[0] == :escape
end