# File lib/compass/sass_extensions/functions/lists.rb, line 4
  def blank(obj)
    case obj
    when Sass::Script::Bool
      Sass::Script::Bool.new !obj.to_bool
    when Sass::Script::String
      Sass::Script::Bool.new obj.value.strip.size == 0
    when Sass::Script::List
      Sass::Script::Bool.new obj.value.size == 0 || obj.value.all?{|el| blank(el).to_bool}
    else
      Sass::Script::Bool.new false
    end
  end