# Why is irb different from script file?

**URL:** <https://www.ruby-forum.com/t/why-is-irb-different-from-script-file/151586>\
**Category:** Ruby\
**Created:** [October 23, 2008, 8:37am UTC](https://www.ruby-forum.com/t/why-is-irb-different-from-script-file/151586 "2008-10-23T08:37:21Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![Kyung\_won\_C](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/47e85d/32.png) [@Kyung\_won\_C](https://www.ruby-forum.com/u/Kyung_won_C)\
**Post date:** [October 23, 2008, 8:37am UTC](https://www.ruby-forum.com/t/why-is-irb-different-from-script-file/151586/1 "2008-10-23T08:37:21Z")

</div>

## in irb

> > def why?  
> > end  
> > =\> nil
> 
> > Object.public\_instance\_methods.include?(“why?”)  
> > =\> true

## in test.rb

def why?  
end  
p Object.private\_instance\_methods.include?(“why?”) # =\> true

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# Help Me^^

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