I use Ruby’s irb shell for everyday activities – as a calculator; for writing small code snippets; trying out code snippets; Ruby class documentation etc. The irb shell can be customized using the .irbrc file, usually located in the users home directory. This is a copy of my .irbrc file that I use on Windows PCs.

#-- for wirble
# wirble is a wonderful gem which add nice features to irb
begin
  ENV['IRB_HISTORY_FILE'] = "c:\ruby\.irb_history"
  # load wirble
  require 'wirble'

  wirble_opts = {
    :skip_prompt => true
  }

  # start wirble
  Wirble.init(wirble_opts)
#  Wirble.colorize [Colorize doesn't seem to work on Windows!]
rescue LoadError => err
  warn "Couldn't load Wirble: #{err}"
end 

# List non-trivial methods on any class
class Object
  # Return only the methods not present on basic objects
  def interesting_methods
    (self.methods - Object.new.methods).sort
  end
end

#-- For Summable
# Add Summable functionality to Arrays and Ranges
module Summable
  def sum
    inject(0) { |x, y| x + y }
  end
end

class Array
  include Summable
end

class Range
  include Summable
end

#-- Simplify converting numbers to hex
module Hexable
  def hex
    '0x' + to_s(16)
  end
end

class Fixnum
  include Hexable
end

class Bignum
  include Hexable
end

# pretty print --> provides a "pretty" view of an object
require 'pp'