rails generate devise user -command not working

When i type: 'rails generate devise user' instead of rails creating files the output is: '/Users/rubyonrails/yopage/yopage/config/routes.rb:3:in block in <top (required)>': undefined methodto' for #<ActionDispatch::Routing::Mapper:0x000001020c1888> (NoMethodError) from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/actionpack-3.2.12/lib/action_dispatch/routing/route_set.rb:282:in instance_exec' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/actionpack-3.2.12/lib/action_dispatch/routing/route_set.rb:282:ineval_block' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/actionpack-3.2.12/lib/action_dispatch/routing/route_set.rb:260:in draw' from /Users/rubyonrails/yopage/yopage/config/routes.rb:1:in<top (required)>' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/activesupport-3.2.12/lib/active_support/dependencies.rb:245:in load' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/activesupport-3.2.12/lib/active_support/dependencies.rb:245:inblock in load' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/activesupport-3.2.12/lib/active_support/dependencies.rb:236:in load_dependency' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/activesupport-3.2.12/lib/active_support/dependencies.rb:245:inload' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/application/routes_reloader.rb:40:in block in load_paths' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/application/routes_reloader.rb:40:ineach' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/application/routes_reloader.rb:40:in load_paths' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/application/routes_reloader.rb:16:inreload!' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/application/routes_reloader.rb:26:in block in updater' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/activesupport-3.2.12/lib/active_support/file_update_checker.rb:78:incall' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/activesupport-3.2.12/lib/active_support/file_update_checker.rb:78:in execute' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/application/routes_reloader.rb:27:inupdater' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/application/routes_reloader.rb:9:in rescue in execute_if_updated' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/application/routes_reloader.rb:7:inexecute_if_updated' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/application/finisher.rb:66:in block in <module:Finisher>' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/initializable.rb:30:ininstance_exec' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/initializable.rb:30:in run' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/initializable.rb:55:inblock in run_initializers' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/initializable.rb:54:in each' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/initializable.rb:54:inrun_initializers' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/application.rb:136:in initialize!' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/railtie/configurable.rb:30:inmethod_missing' from /Users/rubyonrails/yopage/yopage/config/environment.rb:5:in <top (required)>' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/activesupport-3.2.12/lib/active_support/dependencies.rb:251:inrequire' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/activesupport-3.2.12/lib/active_support/dependencies.rb:251:in block in require' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/activesupport-3.2.12/lib/active_support/dependencies.rb:236:inload_dependency' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/activesupport-3.2.12/lib/active_support/dependencies.rb:251:in require' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/application.rb:103:inrequire_environment!' from /usr/local/rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.12/lib/rails/commands.rb:25:in <top (required)>' from script/rails:6:inrequire' from script/rails:6:in `<main>' '