can't convert nil into String /usr/local/ruby/1.8/lib/ruby/1.8/pstore.rb:95:in `dirname' /usr/local/ruby/1.8/lib/ruby/1.8/pstore.rb:95:in `initialize' matome.rb:58:in `new' matome.rb:58:in `get_user' matome.rb:92:in `matome' matome.rb:214