# Pdf is not a class or module

**URL:** <https://www.ruby-forum.com/t/pdf-is-not-a-class-or-module/140396>\
**Category:** Ruby\
**Created:** [June 13, 2008, 4:03pm UTC](https://www.ruby-forum.com/t/pdf-is-not-a-class-or-module/140396 "2008-06-13T16:03:24Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![neha-rohan](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/n/34f0e0/32.png) [@neha-rohan](https://www.ruby-forum.com/u/neha-rohan)\
**Post date:** [June 13, 2008, 4:03pm UTC](https://www.ruby-forum.com/t/pdf-is-not-a-class-or-module/140396/1 "2008-06-13T16:03:24Z")

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Hi,

In our application we have used the pdf writer to give us PDF outputs.  
And we have installed these gems and included them in the environment.rb  
file.

require ‘pdf/writer’  
require ‘pdf/simpletable’

But when we try to generate the pdf, sometimes we get the pdf file as  
result and at other times we get this error:  
pdf is not a class or module.