title: Can I define alias in Rails console
body: <p>I tried to edit my ~/.irbrc file
  and define show_tbls method to fetch the tables I have,
  because the command is to long , so I tried to make a function for easier use.</p>
  
  <pre><code>require 'hirb' ; Hirb.enable
  require 'irb/completion'
  
  def show_tbls
      ActiveRecord::Base.connection.tables
  end
  </code></pre>
  
  <p>When I ran the show_tbls
  it showed the error as followings</p>
  
  <pre><code>1.9.3-p448 :001 &gt; show_tbls()
  NoMethodError: undefined method `show_tbls' for main:Object
          from (irb):1
          from /home/poc/.rvm/gems/ruby-1.9.3-p448/gems/railties-3.2.13/lib/rails/commands/console.rb:47:in `start'
          from /home/poc/.rvm/gems/ruby-1.9.3-p448/gems/railties-3.2.13/lib/rails/commands/console.rb:8:in `start'
          from /home/poc/.rvm/gems/ruby-1.9.3-p448/gems/railties-3.2.13/lib/rails/commands.rb:41:in `&lt;top (required)&gt;'
          from script/rails:6:in `require'
          from script/rails:6:in `&lt;main&gt;'
  1.9.3-p448 :002 &gt; show_tbls
  NameError: undefined local variable or method `show_tbls' for main:Object
  </code></pre>