Irb Tricks

I recently had a discussion with someone(not really familiar with Ruby and its frameworks) and this person didn’t realize the power of IRB and the Rails console.

irb

Not, this irb, the Ruby IRB. According to wikipedia IRB is a shell for programming in the object-oriented scripting language Ruby. IRB is run from the command line and allows the programmer to experiment with code in real time. It allows you to enter Ruby commands at the prompt and have the interpreter respond immediately. It features command history, line editing capabilities, and job control, and is able to communicate directly as a shell script over the Internet and interact with a live server. It was developed by Keiju Ishitsuka.

IRB is awesome and the Rails developers knew it and extended it by creating the Rails console. (come on, you know: $ ruby script/console )

The only issue I have with the Rails console is that it doesn’t have a history. Not really a big deal but don’t worry the console can be extended.

IRB tips and tricks

You can also decide to install wirble a gem compiling most of the tricks from rubygarden.org

Simply do:

<code>sudo gem install wirble
</code>

then edit your ~/.irbrc file and add the following:

<code># load libraries
require 'rubygems'
require 'wirble'
Wirble.init
</code>

or if you want the fancy colors (I personally don’t like using them), your ~/.irbrc file should look like:

<code># load libraries
require 'rubygems'
require 'wirble'

# start wirble (with color)
Wirble.init
Wirble.colorize
</code>

Start your console and you can now use the history by pressing up.

read more about wirble

Tricks I use on a regular basis:

Start a console in a different environment:

<code>$ ruby script/console production
</code>

Reload the console after you modified a class

<code>>> reload!
</code>

Rollback changes on exit:

<code>$ script/console --sandbox
</code>

or

<code>$ script/console -s
</code>

and if feel like a ninja, try the combo which will load the production environment in sanbbox :

<code>$ script/console production -s
</code>

ninja combo

Most Rails developers are really familiar with everything I explained in this post but I realized that too many new comers ignore the great tools provided to them for free. Hopefully this post will help few newbies ;)

By Matt Aimonetti