Interesting Methods Gem

March 23, 2018

I’ve just published a simple new gem called interesting_methods.

After you install and set this up, from within irb and pry, you can type:

MyClass.im
  # &
my_instance.im

to see all the interesting methods available to you on those objects.

To Set Up

First install the gem:

gem install interesting_methods

Then create irb and pry rc files if they don’t already exist:

touch ~/.irbrc
touch ~/.pryrc

Edit each of those rc files and add the following code:

if Gem::Specification.find_all_by_name('interesting_methods').any?
  require 'interesting_methods'
end

You’re all set up now!

To Use

Load up either irb or pry from your command line.

Add .im to any object to see its interesting methods.

Example

Load up pry:

$ pry

You should be at the pry prompt now:

pry >

Paste the following code into pry:

class Animal

  @@all = []

  attr_reader :type, :sound

  def initialize(type, sound)
    @type  = type
    @sound = sound
    @@all << self
  end

  def speak_loudly
    puts @sound.upcase
  end

  def speak
    puts @sound
  end

  def self.all
    @@all
  end

  def self.report
    puts "#{'Type'.rjust(15)} #{'Sound'.rjust(15)}"
    puts "#{'----'.rjust(15)} #{'-----'.rjust(15)}"
    all.each do |animal|
      puts "#{animal.type.rjust(15)} #{animal.sound.rjust(15)}"
    end
  end

end

cow = Animal.new('cow', 'moo')

Now check out the methods on both Animal and cow (an instance of Animal):

pry > Animal.im
=> [:all, :report]

pry > cow.im
=> [:sound, :speak, :speak_loudly, :type]

Repo

You can find the repo at https://github.com/seanlerner/interesting_methods

In my next post, you’ll find a screencast that illustrates a technique I call, Method Driven Development using the gem.

Enjoy!