ruby Fail to load readline

Question

I intend to use Tab Completion, then I try to load readline using the following command:

$ irb -r irb/completion

However, irb throws an error message shown below:

/usr/local/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `require':LoadError: cannot load such file -- readline

Then I try to install readline using command:

gem install readline

But, RubyGems prompt me that

ERROR: Could not find a valid gem 'readline' (>= 0) in any repository

How can I fix it?

Answer 1

You have been troubled by the naming.

The repo name is rb-readline

Answer 2

You need to have the readline libraries installed when you compile Ruby.

Follow this blog: http://vvv.tobiassjosten.net/ruby-on-rails/fixing-readline-for-the-ruby-on-rails-console/