How many times have you thought that debugging is difficult so instead of finding out how to do it you simply started adding puts "var value: #{some_var}" all over your code and even external gems code!

Well i have news for you guys, ruby debug from your terminal is easy.

All you need to start is requiring 'debug' when calling your ruby script or ruby binary:

ruby -r debug your_program.rb

Below, take a look at how i debugged thor gem to add a new config option:

I executed some thor script with ruby -rdebug script.rb then:

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# Set a breakpoint at directory.rb line 80:
break ~/.rbenv/versions/2.0.0-p0/lib/ruby/gems/2.0.0/gems/thor-0.17.0/lib/thor/actions/directory.rb:80
# Now run until program ends or hits a breakpoint
cont
# Take a look at the local variables after hitting that breakpoint:
local_variables
#=> [:file_source, :file_destination, :dirname, :destination, :lookup]
file_source
#=> "~/.newgem-templates/default/.git/description"

Play around in that console as you normally do with irb and..

have fun!!