# File lib/sass/tree/visitors/perform.rb, line 377
  def visit_content(node)
    content, content_env = @environment.content
    return [] unless content
    @environment.stack.with_mixin(node.filename, node.line, '@content') do
      trace_node = Sass::Tree::TraceNode.from_node('@content', node)
      content_env = Sass::Environment.new(content_env)
      content_env.caller = Sass::Environment.new(@environment)
      with_environment(content_env) do
        trace_node.children = content.map {|c| visit(c.dup)}.flatten
      end
      trace_node
    end
  rescue Sass::SyntaxError => e
    e.modify_backtrace(:mixin => '@content', :line => node.line)
    e.add_backtrace(:line => node.line)
    raise e
  end