I come from python background and am learning ruby. IPython is really awesome. I am new to ruby now, and wanted to have some sort of ipython things. As of now am having tough time, going along ruby lines. Seems to be slightly irritating, when pressing tab does not complete things. I hit upon this question and followed the first answer, with max upvotes.

It said to do require 'irb/completion'

I did the same, and got following error:

LoadError: cannot load such file -- readlinefrom /home/letsrock/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'from /home/letsrock/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'from /home/letsrock/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'from /home/letsrock/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'from (irb):1from /home/letsrock/.rvm/rubies/ruby-1.9.3-p194/bin/irb:16:in `<main>'

I then tried require 'completion' which eventually led to the following error:

LoadError: cannot load such file -- completionfrom /home/letsrock/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'from /home/letsrock/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'from (irb):3from /home/letsrock/.rvm/rubies/ruby-1.9.3-p194/bin/irb:16:in `<main>'

Let me know whats wrong, i am using ubuntu 11.04.

Give a look at Pry which is an alternative to IRB.

It has:

Many convenience commands inspired by IPython, Smalltalk and other advanced REPLs

A few of the features include:

• Source code browsing (including core C source with the pry-doc gem)
• Navigation around state (cd, ls and friends)
• Documentation browsing
• Live help system
• Open methods in editors (edit-method Class#method)
• Syntax highlighting
• Command shell integration (start editors, run git, and rake from within Pry)
• Gist integration
• Runtime invocation (use Pry as a developer console or debugger)
• Ability to view and replay history

It is also very actively developed with version 0.9.10 released on 7/14/2012.