adamantium
==========

Create immutable objects

[![Build Status](https://secure.travis-ci.org/dkubb/adamantium.png)](https://travis-ci.org/dkubb/adamantium)
[![Dependency Status](https://gemnasium.com/dkubb/adamantium.png)](https://gemnasium.com/dkubb/adamantium)
[![Code Climate](https://codeclimate.com/github/dkubb/adamantium.png)](https://codeclimate.com/github/dkubb/adamantium)

This is a small standalone gem featuring a module ripped out from [veritas](https://github.com/dkubb/veritas).
It allows to make objects immutable in an unobtrusive way.

Installation
------------

With Rubygems:

```bash
$ gem install adamantium
$ irb -rubygems
>> require 'adamantium'
=> true
```

With git and local working copy:

```bash
$ git clone git://github.com/dkubb/adamantium.git
$ cd adamantium
$ rake install
$ irb -rubygems
>> require 'adamantium'
=> true
```

Examples
--------

``` ruby
require 'adamantium'
require 'securerandom'

class Example
  # Inclusion of Adamantium defaults to deep freeze behavior
  # of constructor and memoizer

  include Adamantium

  # Instance and attributes (ivars) are frozen per default
  # Example:
  #
  # object = Example.new
  # object.frozen?           # => true
  # object.attribute.frozen? # => true
  #
  def initialize
    @attribute = "foo bar"
  end
  attr_reader :attribute

  # Memoized method with deeply frozen value (default)
  # Example:
  #
  # object = Example.new
  # object.random => ["abcdef"]
  # object.random => ["abcdef"]
  # object.random.frozen? => true
  # object.random[0].frozen? => true
  #
  def random
    [SecureRandom.hex(6)]
  end
  memoize :random

  # Memoized method with non frozen value
  # Example:
  #
  # object = Example.new
  # object.buffer         # => <StringIO:abcdef>
  # object.buffer         # => <StringIO:abcdef>
  # object.buffer.frozen? # => false
  #
  def buffer
    StringIO.new
  end
  memoize :buffer, :freezer => :noop

  # Memoized method with nondeeply frozen value
  # Example:
  #
  # object = Example.new
  # object.random2 => ["abcdef"]
  # object.random2 => ["abcdef"]
  # object.random2.frozen? => true
  # object.random2[0].frozen? => false
  #
  def random2
    [SecureRandom.hex(6)]
  end
  memoize :random2, :freezer => :flat
end

class FlatExample
  # Inclusion of Adamantium::Flat defaults do non deep frozen behavior
  # for memoizer and constructor

  include Adamantium::Flat

  # Instace is frozen but attribute is not
  # object = FlatExample.new
  # object.frozen?           # => true
  # object.attribute.frozen? # => false
  def initialize
    @attribute = "foo bar"
  end
  attr_reader :attribute

  # Memoized method with flat frozen value (default)
  # Example:
  #
  # object = Example.new
  # object.random => ["abcdef"]
  # object.random => ["abcdef"]
  # object.random.frozen? => true
  # object.random[0].frozen? => false
  #
  def random
    [SecureRandom.hex(6)]
  end
  memoize :random
end
```

Credits
-------

* Dan Kubb ([dkubb](https://github.com/dkubb))
* Markus Schirp ([mbj](https://github.com/mbj))

Contributing
-------------

* If you want your code merged into the mainline, please discuss the proposed changes with me before doing any work on it. This library is still in early development, and the direction it is going may not always be clear. Some features may not be appropriate yet, may need to be deferred until later when the foundation for them is laid, or may be more applicable in a plugin.
* Fork the project.
* Make your feature addition or bug fix.
  * Follow this [style guide](https://github.com/dkubb/styleguide).
* Add specs for it. This is important so I don't break it in a future version unintentionally. Tests must cover all branches within the code, and code must be fully covered.
* Commit, do not mess with Rakefile, version, or history. (if you want to have your own version, that is fine but bump version in a commit by itself I can ignore when I pull)
* Run "rake ci". This must pass and not show any regressions in the metrics for the code to be merged.
* Send me a pull request. Bonus points for topic branches.

Copyright
---------

Copyright &copy; 2012 Dan Kubb. See LICENSE for details.