# File lib/sass/tree/visitors/perform.rb, line 237
  def visit_mixindef(node)
    env = Sass::Environment.new(@environment, node.options)
    @environment.set_local_mixin(node.name,
      Sass::Callable.new(node.name, node.args, node.splat, env, node.children, node.has_content, "mixin"))
    []
  end