I'm having some trouble with dm-is-list. I'm trying to set the position of a page by using a drop down menu. I have the following code in a Sinatra app: Page.create(params[:page]).move(params[:position])
The strange thing is that I get the error below on the live site on Heroku, but not on my local testing server. I have the exact same gems installed on Heroku as my local machine, so I don't understand why one is throwing an error and the other isn't!! If anybody can help me it would be much appreciated. cheers, DAZ NoMethodError - undefined method `+' for nil:NilClass: /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-is-list-1.0.2/lib/dm-is-list/is/list.rb:544:in `move_without_saving' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-is-list-1.0.2/lib/dm-is-list/is/list.rb:265:in `__send__' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-is-list-1.0.2/lib/dm-is-list/is/list.rb:265:in `is_list' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-core-1.0.2/lib/dm-core/model/hook.rb:77:in `instance_eval' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-core-1.0.2/lib/dm-core/model/hook.rb:77:in `call' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-core-1.0.2/lib/dm-core/resource.rb:1156:in `execute_hooks_for' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-core-1.0.2/lib/dm-core/resource.rb:1156:in `each' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-core-1.0.2/lib/dm-core/resource.rb:1156:in `execute_hooks_for' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-core-1.0.2/lib/dm-core/resource.rb:700:in `before_create_hook' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-core-1.0.2/lib/dm-core/resource.rb:981:in `create_with_hooks' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-core-1.0.2/lib/dm-core/resource.rb:979:in `catch' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-core-1.0.2/lib/dm-core/resource.rb:979:in `create_with_hooks' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-core-1.0.2/lib/dm-core/resource.rb:1033:in `save_self' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-validations-1.0.2/lib/dm-validations.rb:111:in `save_self' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-core-1.0.2/lib/dm-core/resource.rb:1018:in `_save' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-core-1.0.2/lib/dm-core/resource.rb:1234:in `run_once' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-core-1.0.2/lib/dm-core/resource.rb:1017:in `_save' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-core-1.0.2/lib/dm-core/resource.rb:417:in `save' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-validations-1.0.2/lib/dm-validations.rb:98:in `save' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-validations-1.0.2/lib/dm-validations/support/ context.rb:30:in `validation_context' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-validations-1.0.2/lib/dm-validations.rb:98:in `save' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/dm-validations-1.0.2/lib/dm-validations.rb:83:in `create' ./ib.rb:64:in `POST /page' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:1032:in `call' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:1032:in `compile!' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:620:in `instance_eval' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:620:in `route_eval' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:604:in `route!' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:656:in `process_route' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:653:in `catch' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:653:in `process_route' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:603:in `route!' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:602:in `each' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:602:in `route!' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:741:in `dispatch!' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:530:in `call!' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:706:in `instance_eval' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:706:in `invoke' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:706:in `catch' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:706:in `invoke' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:530:in `call!' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:516:in `call' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/rack-1.2.1/lib/rack/methodoverride.rb:24:in `call' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/rack-1.2.1/lib/rack/commonlogger.rb:18:in `call' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:1142:in `call' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:1168:in `synchronize' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/sinatra-1.1.0/lib/sinatra/base.rb:1142:in `call' /home/heroku_rack/lib/static_assets.rb:9:in `call' /home/heroku_rack/lib/last_access.rb:15:in `call' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/rack-1.2.1/lib/rack/urlmap.rb:47:in `call' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/rack-1.2.1/lib/rack/urlmap.rb:41:in `each' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/rack-1.2.1/lib/rack/urlmap.rb:41:in `call' /home/heroku_rack/lib/date_header.rb:14:in `call' /home/slugs/324899_06e826d_32f5-5fd1a6ba-20af-430f-bddf-17162ef8b4ff/ mnt/.gems/gems/rack-1.2.1/lib/rack/builder.rb:77:in `call' /usr/ruby1.8.7/lib/ruby/gems/1.8/gems/thin-1.2.6/lib/thin/ connection.rb:76:in `pre_process' /usr/ruby1.8.7/lib/ruby/gems/1.8/gems/thin-1.2.6/lib/thin/ connection.rb:74:in `catch' /usr/ruby1.8.7/lib/ruby/gems/1.8/gems/thin-1.2.6/lib/thin/ connection.rb:74:in `pre_process' /usr/ruby1.8.7/lib/ruby/gems/1.8/gems/thin-1.2.6/lib/thin/ connection.rb:57:in `process' /usr/ruby1.8.7/lib/ruby/gems/1.8/gems/thin-1.2.6/lib/thin/ connection.rb:42:in `receive_data' /usr/ruby1.8.7/lib/ruby/gems/1.8/gems/eventmachine-0.12.10/lib/ eventmachine.rb:256:in `run_machine' /usr/ruby1.8.7/lib/ruby/gems/1.8/gems/eventmachine-0.12.10/lib/ eventmachine.rb:256:in `run' /usr/ruby1.8.7/lib/ruby/gems/1.8/gems/thin-1.2.6/lib/thin/backends/ base.rb:57:in `start' /usr/ruby1.8.7/lib/ruby/gems/1.8/gems/thin-1.2.6/lib/thin/server.rb: 156:in `start' /usr/ruby1.8.7/lib/ruby/gems/1.8/gems/thin-1.2.6/lib/thin/controllers/ controller.rb:80:in `start' /usr/ruby1.8.7/lib/ruby/gems/1.8/gems/thin-1.2.6/lib/thin/runner.rb: 177:in `send' /usr/ruby1.8.7/lib/ruby/gems/1.8/gems/thin-1.2.6/lib/thin/runner.rb: 177:in `run_command' /usr/ruby1.8.7/lib/ruby/gems/1.8/gems/thin-1.2.6/lib/thin/runner.rb: 143:in `run!' /usr/ruby1.8.7/lib/ruby/gems/1.8/gems/thin-1.2.6/bin/thin:6 /usr/ruby1.8.7/bin/thin:19:in `load' /usr/ruby1.8.7/bin/thin:19 -- You received this message because you are subscribed to the Google Groups "Heroku" group. 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