# File lib/sass/script/functions.rb, line 1916 def join(list1, list2, separator = identifier("auto")) assert_type separator, :String, :separator unless %w(auto space comma).include?(separator.value) raise ArgumentError.new("Separator name must be space, comma, or auto") end sep = if separator.value == 'auto' list1.separator || list2.separator || :space else separator.value.to_sym end list(list1.to_a + list2.to_a, sep) end