# SimplaTable with error: singleton can't be dumped

**URL:** <https://www.ruby-forum.com/t/simplatable-with-error-singleton-cant-be-dumped/106348>\
**Category:** Rails\
**Created:** [June 8, 2007, 8:50pm UTC](https://www.ruby-forum.com/t/simplatable-with-error-singleton-cant-be-dumped/106348 "2007-06-08T20:50:16Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![helderam](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/aeb1de/32.png) [@helderam](https://www.ruby-forum.com/u/helderam)\
**Post date:** [June 8, 2007, 8:50pm UTC](https://www.ruby-forum.com/t/simplatable-with-error-singleton-cant-be-dumped/106348/1 "2007-06-08T20:50:16Z")

</div>

Hello,

My first PDF report from rails.

When i try to render “tab.render\_on(pdf)”, I get that error message.

Thanks any help,

Helder

=================================================================  
TypeError in ContasController#plano

singleton can’t be dumped

RAILS\_ROOT: script/…/config/…  
Application Trace | Framework Trace | Full Trace

/var/lib/gems/1.8/gems/transaction-simple-1.4.0/lib/transaction/simple.rb:129:in  
`dump' /var/lib/gems/1.8/gems/transaction-simple-1.4.0/lib/transaction/simple.rb:129:in`start\_transaction’  
/var/lib/gems/1.8/gems/transaction-simple-1.4.0/lib/transaction/simple/group.rb:102:in  
`start_transaction' /var/lib/gems/1.8/gems/transaction-simple-1.4.0/lib/transaction/simple/group.rb:102:in`each’  
/var/lib/gems/1.8/gems/transaction-simple-1.4.0/lib/transaction/simple/group.rb:102:in  
`start_transaction' /var/lib/gems/1.8/gems/pdf-writer-1.1.3/lib/pdf/simpletable.rb:397:in`render\_on’  
app/controllers/contas\_controller.rb:64:in `plano' /var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/base.rb:1095:in`send’  
/var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action\_controller/base.rb:1095:in  
`perform_action_without_filters' /var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:632:in`call\_filter’  
/var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action\_controller/filters.rb:634:in  
`call_filter' /var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:638:in`call\_filter’  
/var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action\_controller/filters.rb:438:in  
`call' /var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:637:in`call\_filter’  
/var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action\_controller/filters.rb:638:in  
`call_filter' /var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:438:in`call’  
/var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action\_controller/filters.rb:637:in  
`call_filter' /var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:619:in`perform\_action\_without\_benchmark’  
/var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action\_controller/benchmarking.rb:66:in  
`perform_action_without_rescue' /var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/benchmarking.rb:66:in`perform\_action\_without\_rescue’  
/var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action\_controller/rescue.rb:83:in  
`perform_action' /var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/base.rb:430:in`send’  
/var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action\_controller/base.rb:430:in  
`process_without_filters' /var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:624:in`process\_without\_session\_management\_support’  
/var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action\_controller/session\_management.rb:114:in  
`process' /var/lib/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/base.rb:330:in`process’  
/var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel/rails.rb:78:in  
`process' /var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel/rails.rb:76:in`synchronize’  
/var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel/rails.rb:76:in  
`process' /var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel.rb:618:in`process\_client’  
/var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel.rb:617:in `each' /var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel.rb:617:in`process\_client’  
/var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel.rb:736:in `run' /var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel.rb:736:in`initialize’  
/var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel.rb:736:in `new' /var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel.rb:736:in`run’  
/var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel.rb:720:in `initialize' /var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel.rb:720:in`new’  
/var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel.rb:720:in `run' /var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel/configurator.rb:271:in`run’  
/var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel/configurator.rb:270:in  
`each' /var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel/configurator.rb:270:in`run’  
/var/lib/gems/1.8/gems/mongrel-1.0.1/bin/mongrel\_rails:127:in `run' /var/lib/gems/1.8/gems/mongrel-1.0.1/lib/mongrel/command.rb:211:in`run’  
/var/lib/gems/1.8/gems/mongrel-1.0.1/bin/mongrel\_rails:243  
/var/lib/gems/1.8/gems/activesupport-1.4.2/lib/active\_support/dependencies.rb:488:in  
`load' /var/lib/gems/1.8/gems/activesupport-1.4.2/lib/active_support/dependencies.rb:488:in`load’  
/var/lib/gems/1.8/gems/activesupport-1.4.2/lib/active\_support/dependencies.rb:342:in  
`new_constants_in' /var/lib/gems/1.8/gems/activesupport-1.4.2/lib/active_support/dependencies.rb:488:in`load’  
/var/lib/gems/1.8/gems/rails-1.2.3/lib/commands/servers/mongrel.rb:60  
/var/lib/gems/1.8/gems/activesupport-1.4.2/lib/active\_support/dependencies.rb:495:in  
`require' /var/lib/gems/1.8/gems/activesupport-1.4.2/lib/active_support/dependencies.rb:342:in`new\_constants\_in’  
/var/lib/gems/1.8/gems/activesupport-1.4.2/lib/active\_support/dependencies.rb:495:in  
`require’  
/var/lib/gems/1.8/gems/rails-1.2.3/lib/commands/server.rb:39