TypeWrapper
Delegator pattern in Ruby without object schizophrenia. Because Object#extend at runtime is evil.
Installation
Add this line to your application's Gemfile:
gem 'type_wrapper'
And then execute:
$ bundle
Or install it yourself as:
$ gem install type_wrapper
Usage
module ToArray
def to_a
[self]
end
end
module ToString
def to_s
"#{self}"
end
end
Person = Struct.new(:name)
PersonPresenter = TypeWrapper[Person, ToArray, ToString]
peter = PersonPresenter.new(Person.new('Peter'))
peter.to_a
Pros
- Five (5) times faster than Object#extend.
- Delegation without self schizophrenia.
- Decorator Pattern with multiple traits.
- Allows DCI in Ruby without blowing the method cache at run time.
Cons
- Three (3) times slower than calling class method. See benchmark.
- Procedural code inside Mixin is broken, methods scoped in Mixin cannot directly call another method in the same scope of the Mixin.
- Methods applied by Object#extend takes precedence over Mixin methods.
Development
After checking out the repo, run bin/setup
to install dependencies. Then, run rake test
to run the tests. You can also run bin/console
for an interactive prompt that will allow you to experiment.
To install this gem onto your local machine, run bundle exec rake install
. To release a new version, update the version number in version.rb
, and then run bundle exec rake release
, which will create a git tag for the version, push git commits and tags, and push the .gem
file to rubygems.org.
Contributing
Bug reports and pull requests are welcome on GitHub at https://github.com/RichOrElse/type_wrapper.
License
The gem is available as open source under the terms of the MIT License.