Izzy

Izzy Module

To demo Izzy, let's take our class, Person:

class Person
  include Izzy # Make sure to include Izzy!
  attr_reader :name, :age, :sex

  def initialize(name, age, sex)
    @name = name
    @age  = age
    @sex  = sex
  end

  def older_than_18?; @age > 18 end

  def younger_than_18?; @age < 18 end

  def male?; @sex == 'm'; end

  def female?; @sex == 'f' end

  def me?; @name == 'brandon' && @sex == 'm' end

  def geek?; @name == 'brandon' end
end

So we make our person:

brandon = Person.new('brandon', 23, 'm')

...and do some comparisons!

brandon.all_of?  :older_than_18?, :male?, :me?, :geek? # => true
brandon.none_of? :younger_than_18?, :female?           # => true
brandon.any_of?  :male?, :female?, :geek?              # => true

Maybe boolean comparisons aren't your cup of tea. Izzy has you covered my friend:

brandon.matches_all?  name: /^br/, age: (20..30) # => true
brandon.matches_any?  name: /br$/, age: (20..30) # => true
brandon.matches_none? name: /br&/, age: (30..40) # => true

Izzy compares on === much like a case statement, allowing you to regex and range away! You can even do type checks while you're at it.

brandon.matches_all? name: String, age: Integer

Why stop there? Need a bit more power? We have Lambdas for that!

longer_than_3 = -> n { n.length > 3 }
is_odd = -> a { a.odd? }

brandon.matches_all? name: longer_than_3, age: is_odd # => true

....or let's push it further for some interesting results:

longer_than_5 = -> n { n.length > 5 }
greater_than_20 = -> a { a > 20 }

brandon.matches_all?(
  name: [/br/, /an/, longer_than_5],
  age: [(20..30), greater_than_20]
)

# => true

Simple to the point, no more mess of && or || checks for the same object. All you have to do is include Izzy in your object and you're ready to go!

Izzy Array Module

But wait! There's more! IzzyArray allows you a few more tricks on top of that!

class Array; include IzzyArray end

[0,0,0].all_are :zero?       # => true
[0,nil,'foo'].any_are :zero? # => true
[0,0,0].none_are :nil?       # => true

Combine with rails :present?, :empty?, and various other methods and you have some interesting results! This one will get some more power with experimentation.

Installation

Add this line to your application's Gemfile:

gem 'izzy'

And then execute:

$ bundle

Or install it yourself as:

$ gem install izzy

Usage

It patches object, just use it with any method that matches the pattern is_foo? and you're good to go!

Contributing

1. Fork it ( http://github.com/baweaver/izzy/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request